From 7bbe33725f45a55d8009964e2f50c27f50a21cdc Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:00:51 +0100
Subject: [PATCH 1/6] fix(backend): remove card from player before calling
 PlayCard

---
 backend/api/websocket.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/backend/api/websocket.go b/backend/api/websocket.go
index 5a75abd..55ceee1 100644
--- a/backend/api/websocket.go
+++ b/backend/api/websocket.go
@@ -248,7 +248,7 @@ func onPlayerJoin(client *socketio.Socket, room *types.Room, player *types.Playe
 			return
 		}
 		card := player.Cards[*updatePlayerRequest.CardIndex]
-		if !room.CardDeck.PlayCard(card) {
+		if !room.CardDeck.CanPlay(card) {
 			client.Emit("Status", types.S2C_Status{
 				IsError:    true,
 				StatusCode: "card_not_playable",
@@ -257,6 +257,9 @@ func onPlayerJoin(client *socketio.Socket, room *types.Room, player *types.Playe
 			return
 		}
 		player.Cards = append(player.Cards[:*updatePlayerRequest.CardIndex], player.Cards[*updatePlayerRequest.CardIndex+1:]...)
+		if !room.CardDeck.PlayCard(card) {
+			slog.Error("Cannot play card after checking", "roomId", room.RoomId.Hex(), "playerId", player.PlayerId.Hex())
+		}
 		game.OnPlayCard(room, player, *updatePlayerRequest.CardIndex, card)
 
 		if len(player.Cards) == 0 {

From 4104b01978e2ece1a5b3039867940fb6533aab6c Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:03:18 +0100
Subject: [PATCH 2/6] feat(backend): implement changing card deck

---
 backend/api/websocket.go           | 30 ++++++++++++++++++++++++++++++
 backend/game/game.go               | 20 +++++++++++++++++++-
 backend/types/websocket_packets.go |  3 +++
 3 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/backend/api/websocket.go b/backend/api/websocket.go
index 55ceee1..c18c2de 100644
--- a/backend/api/websocket.go
+++ b/backend/api/websocket.go
@@ -95,6 +95,36 @@ func onPlayerJoin(client *socketio.Socket, room *types.Room, player *types.Playe
 		game.OnRoomUpdate(room)
 	})
 
+	client.On("SetCardDeck", func(datas ...any) {
+		setCardDeckRequest := types.C2S_SetCardDeck{}
+		unpackData(datas, &setCardDeckRequest)
+
+		if room.GameState != types.StateLobby {
+			client.Emit("Status", types.S2C_Status{
+				IsError:    true,
+				StatusCode: "game_already_running",
+				Message:    "You can't change the card deck while the game is running",
+			})
+			return
+		}
+		if !player.HasPermissionBit(types.PermissionHost) {
+			client.Emit("Status", types.S2C_Status{
+				IsError:    true,
+				StatusCode: "insufficient_permission",
+				Message:    "You can't change the card deck unless you are host",
+			})
+			return
+		}
+		if !game.SetCardDeck(room, setCardDeckRequest.CardDeckId) {
+			client.Emit("Status", types.S2C_Status{
+				IsError:    true,
+				StatusCode: "invalid_card_deck",
+				Message:    "No card deck exists with this ID",
+			})
+			return
+		}
+	})
+
 	client.On("UpdatePlayer", func(datas ...any) {
 		player.Mutex.Lock()
 		defer player.Mutex.Unlock()
diff --git a/backend/game/game.go b/backend/game/game.go
index 9792ea0..2ee1613 100644
--- a/backend/game/game.go
+++ b/backend/game/game.go
@@ -123,6 +123,24 @@ func UpdateGameState(room *types.Room, newState types.GameState) {
 	OnRoomUpdate(room)
 }
 
+func SetCardDeck(room *types.Room, id int) bool {
+	if id < 0 || id > 1 {
+		return false
+	}
+	room.CardDeckId = id
+	OnRoomUpdate(room)
+	return true
+}
+
+func CreateCardDeckObj(room *types.Room) {
+	switch room.CardDeckId {
+	case 0:
+		room.CardDeck = &decks.Classic{}
+	case 1:
+		room.CardDeck = &decks.HexV1{}
+	}
+}
+
 func BroadcastInRoom(room *types.Room, topic string, data interface{}) {
 	for _, player := range room.Players {
 		if !player.Connection.IsConnected || player.Connection.Socket == nil {
@@ -179,7 +197,7 @@ func StartGame(room *types.Room) {
 	if room.GameState != types.StateLobby {
 		return
 	}
-	room.CardDeck = &decks.Classic{}
+	CreateCardDeckObj(room)
 	room.CardDeck.Init(room)
 	UpdateGameState(room, types.StateRunning)
 	UpdateAllPlayers(room)
diff --git a/backend/types/websocket_packets.go b/backend/types/websocket_packets.go
index 77b649f..16f917e 100644
--- a/backend/types/websocket_packets.go
+++ b/backend/types/websocket_packets.go
@@ -47,6 +47,9 @@ type S2C_PlayedCardUpdate struct {
 	Card      Card
 }
 
+type C2S_SetCardDeck struct {
+	CardDeckId int
+}
 type C2S_UpdatePlayer struct {
 	PlayerId    bson.ObjectID
 	Username    *string

From 2cfcd0089fbb44394a2ee51282e56073baee2b8d Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:05:10 +0100
Subject: [PATCH 3/6] feat(deck-hexv1): implement experimental HexV1 card deck

---
 backend/decks/decks.go |   8 ++
 backend/decks/hexv1.go | 205 +++++++++++++++++++++++++++++++++++++++++
 backend/game/game.go   |   2 +-
 backend/utils/utils.go |   3 +
 4 files changed, 217 insertions(+), 1 deletion(-)
 create mode 100644 backend/decks/hexv1.go

diff --git a/backend/decks/decks.go b/backend/decks/decks.go
index 8b61151..0cb27f8 100644
--- a/backend/decks/decks.go
+++ b/backend/decks/decks.go
@@ -13,6 +13,10 @@ func DeckFromInterface(cardDeckId int, cardDeck bson.D) types.CardDeck {
 		deck := Classic{}
 		bson.Unmarshal(bsonBytes, &deck)
 		return &deck
+	case 1:
+		deck := HexV1{}
+		bson.Unmarshal(bsonBytes, &deck)
+		return &deck
 	}
 
 	return nil
@@ -26,6 +30,10 @@ func CardFromInterface(cardDeckId int, card bson.D) types.Card {
 		deck := ClassicCard{}
 		bson.Unmarshal(bsonBytes, &deck)
 		return &deck
+	case 1:
+		deck := HexV1Card{}
+		bson.Unmarshal(bsonBytes, &deck)
+		return &deck
 	}
 	return nil
 }
diff --git a/backend/decks/hexv1.go b/backend/decks/hexv1.go
new file mode 100644
index 0000000..fab58ac
--- /dev/null
+++ b/backend/decks/hexv1.go
@@ -0,0 +1,205 @@
+package decks
+
+import (
+	"fmt"
+	"math/rand/v2"
+
+	"github.com/HexCardGames/HexDeck/types"
+	"github.com/HexCardGames/HexDeck/utils"
+)
+
+type HexV1 struct {
+	room        *types.Room
+	CardsPlayed []*HexV1Card
+	PlayerOrder []int
+	ActiveIndex int
+}
+
+type HexV1Card struct {
+	Symbol       string
+	Color        string
+	NumericValue int
+}
+
+var HexV1Colors = []string{"blue", "green", "yellow", "purple"}
+var HexV1ActionCards = []string{"shuffle", "skip", "draw", "swap"}
+
+func (deck *HexV1) Init(room *types.Room) {
+	deck.room = room
+	deck.PlayerOrder = make([]int, len(room.Players))
+	deck.ActiveIndex = 0
+
+	deck.room.PlayersMutex.Lock()
+	defer deck.room.PlayersMutex.Unlock()
+	for i, player := range deck.room.Players {
+		deck.PlayerOrder[i] = i
+		player.Mutex.Lock()
+		defer player.Mutex.Unlock()
+		deck.drawMany(player, 8)
+	}
+}
+
+func (deck *HexV1) SetRoom(room *types.Room) {
+	deck.room = room
+}
+
+func (deck *HexV1) IsEmpty() bool {
+	return false
+}
+
+func (deck *HexV1) getTopCard() *HexV1Card {
+	if len(deck.CardsPlayed) == 0 {
+		return nil
+	}
+	return deck.CardsPlayed[len(deck.CardsPlayed)-1]
+}
+
+func (deck *HexV1) GetTopCard() types.Card {
+	return deck.getTopCard()
+}
+
+func (deck *HexV1) generateCard() *HexV1Card {
+	cardType := rand.IntN(16 + len(HexV1ActionCards))
+	cardColor := HexV1Colors[rand.IntN(len(HexV1Colors))]
+	if cardType < 16 {
+		return &HexV1Card{
+			Symbol:       fmt.Sprintf("%x", cardType),
+			Color:        cardColor,
+			NumericValue: cardType,
+		}
+	}
+	cardSymbol := HexV1ActionCards[cardType-16]
+	if rand.IntN(100) <= 10 {
+		cardColor = "rainbow"
+	}
+	return &HexV1Card{
+		Symbol:       "action:" + cardSymbol,
+		Color:        cardColor,
+		NumericValue: 3,
+	}
+}
+
+func (deck *HexV1) drawCard(player *types.Player) types.Card {
+	card := deck.generateCard()
+	player.Cards = append(player.Cards, card)
+	return card
+}
+
+func (deck *HexV1) drawMany(player *types.Player, cards int) {
+	for i := 0; i < cards; i++ {
+		deck.drawCard(player)
+	}
+}
+
+func (deck *HexV1) DrawCard() types.Card {
+	// Can't draw another card before wildcard color is selected
+	topCard := deck.getTopCard()
+	if topCard != nil && topCard.Color == "rainbow" {
+		return nil
+	}
+
+	card := deck.drawCard(deck.getPlayer(deck.ActiveIndex))
+	deck.nextPlayer()
+	return card
+}
+
+func (deck *HexV1) getNextValidIndex(index int) int {
+	if len(deck.room.Players) == 0 || len(deck.PlayerOrder) == 0 {
+		return -1
+	}
+	checkIndex := utils.Mod(index, len(deck.PlayerOrder))
+	for deck.PlayerOrder[checkIndex] >= len(deck.room.Players) {
+		checkIndex = utils.Mod(checkIndex+1, len(deck.PlayerOrder))
+	}
+	return checkIndex
+}
+
+func (deck *HexV1) getPlayer(index int) *types.Player {
+	playerIndex := deck.getNextValidIndex(index)
+	if playerIndex == -1 {
+		return nil
+	}
+	return deck.room.Players[deck.PlayerOrder[playerIndex]]
+}
+
+func (deck *HexV1) getNextPlayerIndex() int {
+	return deck.getNextValidIndex(deck.ActiveIndex + 1)
+}
+
+func (deck *HexV1) nextPlayer() {
+	deck.ActiveIndex = deck.getNextPlayerIndex()
+}
+
+func (deck *HexV1) IsPlayerActive(target *types.Player) bool {
+	return deck.getPlayer(deck.ActiveIndex) == target
+}
+
+func (deck *HexV1) CanPlay(card types.Card) bool {
+	topCard := deck.getTopCard()
+	checkCard := card.(*HexV1Card)
+	if topCard == nil || checkCard == nil {
+		return topCard == nil
+	}
+	return topCard.Color != "rainbow" && (checkCard.Color == "rainbow" || checkCard.Color == topCard.Color || checkCard.Symbol == topCard.Symbol)
+}
+
+func (deck *HexV1) PlayCard(card types.Card) bool {
+	if !deck.CanPlay(card) {
+		return false
+	}
+	deckCard := card.(*HexV1Card)
+	targetPlayer := deck.getPlayer(deck.ActiveIndex)
+	nextPlayer := deck.getPlayer(deck.getNextPlayerIndex())
+
+	if deckCard.Symbol == "action:skip" && deckCard.Color != "rainbow" {
+		deck.nextPlayer()
+	} else if deckCard.Symbol == "action:draw" {
+		amount := 3
+		topCard := deck.getTopCard()
+		if topCard != nil {
+			amount = topCard.NumericValue
+		}
+		deck.drawMany(nextPlayer, amount)
+	} else if deckCard.Symbol == "action:shuffle" {
+		utils.ShuffleSlice(&deck.PlayerOrder)
+	} else if deckCard.Symbol == "action:swap" {
+		p1Cards := targetPlayer.Cards
+		p2Cards := nextPlayer.Cards
+		targetPlayer.Cards = p2Cards
+		nextPlayer.Cards = p1Cards
+	}
+
+	if deckCard.Color != "rainbow" {
+		deck.nextPlayer()
+	}
+
+	deck.CardsPlayed = append(deck.CardsPlayed, deckCard)
+	return true
+}
+
+func (deck *HexV1) UpdatePlayedCard(cardData interface{}) types.Card {
+	topCard := deck.getTopCard()
+	if topCard.Color != "rainbow" {
+		return nil
+	}
+	updateData, ok := cardData.(map[string]interface{})
+	if !ok {
+		return nil
+	}
+	newColor, ok := updateData["Color"].(string)
+	if !ok {
+		return nil
+	}
+
+	for _, color := range HexV1Colors {
+		if newColor == color {
+			deck.nextPlayer()
+			if topCard.Symbol == "action:skip" {
+				deck.nextPlayer()
+			}
+			topCard.Color = color
+			return topCard
+		}
+	}
+	return nil
+}
diff --git a/backend/game/game.go b/backend/game/game.go
index 2ee1613..f72ae18 100644
--- a/backend/game/game.go
+++ b/backend/game/game.go
@@ -39,7 +39,7 @@ func CreateRoom() *types.Room {
 		GameState:    types.StateLobby,
 		Players:      make([]*types.Player, 0),
 		PlayersMutex: &sync.Mutex{},
-		CardDeckId:   0,
+		CardDeckId:   1,
 	}
 
 	db.Conn.InsertRoom(newRoom)
diff --git a/backend/utils/utils.go b/backend/utils/utils.go
index 44a5044..8a2c6da 100644
--- a/backend/utils/utils.go
+++ b/backend/utils/utils.go
@@ -34,5 +34,8 @@ func ShuffleSlice[T any](slice *([]T)) {
 }
 
 func Mod(a, b int) int {
+	if b == 0 {
+		return 0
+	}
 	return (a%b + b) % b
 }

From 338710d76227dc0b37d44aed514bae0a94210ced Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:25:30 +0100
Subject: [PATCH 4/6] feat(deck-hexv1): add HexV1Card component

---
 .../src/components/Cards/HexV1Card.svelte     | 110 ++++++++++++++++++
 frontend/src/views/Game/Main.svelte           |   3 +-
 2 files changed, 112 insertions(+), 1 deletion(-)
 create mode 100644 frontend/src/components/Cards/HexV1Card.svelte

diff --git a/frontend/src/components/Cards/HexV1Card.svelte b/frontend/src/components/Cards/HexV1Card.svelte
new file mode 100644
index 0000000..a23e034
--- /dev/null
+++ b/frontend/src/components/Cards/HexV1Card.svelte
@@ -0,0 +1,110 @@
+<script lang="ts">
+    import type { Card } from "../../stores/sessionStore";
+
+    interface ClassicCard {
+        Symbol: string;
+        Color: string;
+    }
+    export let data: ClassicCard = { Color: "", Symbol: "" };
+    export let canUpdateCard: boolean = false;
+    export let updateCard: (newCard: Card) => void = () => {};
+    export let width: number;
+    export let height: number;
+
+    const COLOR_MAP: { [key: string]: string } = {
+        blue: "#009bff",
+        green: "#00c841",
+        yellow: "#ffa500",
+        purple: "#7300c8",
+        rainbow: "#ababab",
+        black: "#000000",
+        "": "#999",
+    };
+
+    function selectColor(color: string) {
+        let newCard: ClassicCard = {
+            Color: color,
+            Symbol: data.Symbol,
+        };
+        updateCard(newCard);
+    }
+</script>
+
+<div class="card" style:background={COLOR_MAP[data.Color]} style:--width={`${width}px`} style:--height={`${height}px`}>
+    {#if data.Symbol.length <= 2}
+        <span class="symbol">{data.Symbol}</span>
+    {:else}
+        <span class="symbol large">{data.Symbol.split(":")[1].replace("_", " ")}</span>
+    {/if}
+    {#if data.Color == "rainbow" && canUpdateCard}
+        <div class="select mt-5">
+            <div>
+                <button
+                    style:background={COLOR_MAP["blue"]}
+                    aria-label="Blue"
+                    on:click={() => {
+                        selectColor("blue");
+                    }}
+                ></button>
+                <button
+                    style:background={COLOR_MAP["green"]}
+                    aria-label="Green"
+                    on:click={() => {
+                        selectColor("green");
+                    }}
+                ></button>
+            </div>
+            <div>
+                <button
+                    style:background={COLOR_MAP["yellow"]}
+                    aria-label="Yellow"
+                    on:click={() => {
+                        selectColor("yellow");
+                    }}
+                ></button>
+                <button
+                    style:background={COLOR_MAP["purple"]}
+                    aria-label="Purple"
+                    on:click={() => {
+                        selectColor("purple");
+                    }}
+                ></button>
+            </div>
+        </div>
+    {/if}
+</div>
+
+<style>
+    .card {
+        display: flex;
+        flex-direction: column;
+        width: var(--width);
+        height: var(--height);
+        padding: 5px;
+        border-radius: 8px;
+    }
+
+    .select button {
+        width: 20px;
+        height: 20px;
+        border-radius: 30px;
+    }
+
+    .card span {
+        text-align: left;
+        word-wrap: anywhere;
+    }
+
+    .card .symbol {
+        font-size: 25px;
+        text-transform: capitalize;
+    }
+
+    .card .symbol.large {
+        font-size: 17px;
+    }
+
+    button {
+        cursor: pointer;
+    }
+</style>
diff --git a/frontend/src/views/Game/Main.svelte b/frontend/src/views/Game/Main.svelte
index 3f179d7..828279a 100644
--- a/frontend/src/views/Game/Main.svelte
+++ b/frontend/src/views/Game/Main.svelte
@@ -5,12 +5,13 @@
     import CardDisplay from "../../components/Game/CardDisplay.svelte";
     import { sessionStore } from "../../stores/sessionStore";
     import OpponentDisplay from "../../components/Game/OpponentDisplay.svelte";
+    import HexV1Card from "../../components/Cards/HexV1Card.svelte";
 
     let maxRotationDeg = 20;
     let centerDistancePx = 200;
     let cardWidth = 100;
     let cardHeight = 150;
-    let cardComponent = ClassicCard;
+    let cardComponent = [ClassicCard, HexV1Card][$sessionStore.cardDeckId ?? 0];
 
     let opponents = derived(sessionStore.store, ($store) => $store.players.filter((e) => e.PlayerId != sessionStore.getUserId()));
     let playerActive = derived(sessionStore.store, ($store) => ($store.playerStates[$store.userId ?? ""] ?? "").Active ?? false);

From 6349d5055fc9ca7ed4c96603bb327dfa2df03421 Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:30:25 +0100
Subject: [PATCH 5/6] fix(frontend): fix incorrect parameter in german
 game_status string

---
 frontend/src/i18n/de.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/frontend/src/i18n/de.json b/frontend/src/i18n/de.json
index ed3d1f2..f8a9941 100644
--- a/frontend/src/i18n/de.json
+++ b/frontend/src/i18n/de.json
@@ -83,7 +83,7 @@
         "disconnected": "Getrennt"
     },
     "game_status": {
-        "game_status": "Spielstatus: {game_status}",
+        "game_status": "Spielstatus:",
         "lobby": "Lobby",
         "running": "Läuft",
         "ended": "Beendet"

From 0d3b42193fb60f0f9bdbefbe7e2d4ea2ccc34d7f Mon Sep 17 00:00:00 2001
From: minie4 <minie4@gmx.de>
Date: Fri, 28 Mar 2025 00:32:03 +0100
Subject: [PATCH 6/6] feat(frontend): implement changing the active card deck

---
 .../src/components/CardDeckShowcase.svelte    | 29 ++++++
 frontend/src/i18n/de.json                     |  8 +-
 frontend/src/i18n/en.json                     |  6 +-
 frontend/src/routes/Game.svelte               | 11 ++-
 frontend/src/routes/_module.svelte            |  2 +-
 frontend/src/stores/cardDeck.ts               | 13 +++
 frontend/src/stores/sessionStore.ts           | 11 +++
 frontend/src/views/Game/Lobby.svelte          | 98 +++++++++++++++----
 frontend/src/views/Game/Main.svelte           | 13 ++-
 9 files changed, 158 insertions(+), 33 deletions(-)
 create mode 100644 frontend/src/components/CardDeckShowcase.svelte
 create mode 100644 frontend/src/stores/cardDeck.ts

diff --git a/frontend/src/components/CardDeckShowcase.svelte b/frontend/src/components/CardDeckShowcase.svelte
new file mode 100644
index 0000000..f2197a8
--- /dev/null
+++ b/frontend/src/components/CardDeckShowcase.svelte
@@ -0,0 +1,29 @@
+<script lang="ts">
+    import CardDisplay from "./Game/CardDisplay.svelte";
+
+    export let cardComponent;
+    export let cardDeckId: number;
+    export let cardWidth: number;
+    export let cardHeight: number;
+    export let centerDistancePx: number;
+    export let maxRotationDeg: number;
+
+    const SHOWCASED_CARDS: any = {
+        0: [
+            { CanPlay: true, Card: { Symbol: "1", Color: "red" } },
+            { CanPlay: true, Card: { Symbol: "9", Color: "green" } },
+            { CanPlay: true, Card: { Symbol: "action:draw_2", Color: "blue" } },
+            { CanPlay: true, Card: { Symbol: "action:skip", Color: "yellow" } },
+            { CanPlay: true, Card: { Symbol: "action:draw_4", Color: "black" } },
+        ],
+        1: [
+            { CanPlay: true, Card: { Symbol: "1", Color: "blue" } },
+            { CanPlay: true, Card: { Symbol: "F", Color: "green" } },
+            { CanPlay: true, Card: { Symbol: "action:shuffle", Color: "yellow" } },
+            { CanPlay: true, Card: { Symbol: "action:skip", Color: "purple" } },
+            { CanPlay: true, Card: { Symbol: "action:draw", Color: "rainbow" } },
+        ],
+    };
+</script>
+
+<CardDisplay canPlayCards={true} canUpdateCards={false} {cardComponent} cards={SHOWCASED_CARDS[cardDeckId]} {cardWidth} {cardHeight} {centerDistancePx} {maxRotationDeg} />
diff --git a/frontend/src/i18n/de.json b/frontend/src/i18n/de.json
index f8a9941..32e884f 100644
--- a/frontend/src/i18n/de.json
+++ b/frontend/src/i18n/de.json
@@ -69,7 +69,13 @@
         "player_name": "Spielername",
         "status": "Status",
         "host": "Host",
-        "you": "Du"
+        "you": "Du",
+        "player": "Spieler",
+        "return_to_game": "Zurück zum Spiel",
+        "selected_card_deck": "Ausgewähltes Kartendeck:",
+        "change_card_deck": "Ändern",
+        "choose_card_deck": "Auswählen",
+        "card_deck_modal": "Wähle ein Kartendeck aus"
     },
     "end_screen": {
         "game_has_ended": "Das Spiel ist vorbei",
diff --git a/frontend/src/i18n/en.json b/frontend/src/i18n/en.json
index 8b896d7..1b7b5c3 100644
--- a/frontend/src/i18n/en.json
+++ b/frontend/src/i18n/en.json
@@ -71,7 +71,11 @@
         "host": "Host",
         "you": "You",
         "player": "Player",
-        "return_to_game": "Return to game"
+        "return_to_game": "Return to game",
+        "selected_card_deck": "Selected card deck:",
+        "change_card_deck": "Change",
+        "choose_card_deck": "Choose",
+        "card_deck_modal": "Select a card deck"
     },
     "end_screen": {
         "game_has_ended": "The game has ended",
diff --git a/frontend/src/routes/Game.svelte b/frontend/src/routes/Game.svelte
index 5a18df4..aac716a 100644
--- a/frontend/src/routes/Game.svelte
+++ b/frontend/src/routes/Game.svelte
@@ -10,6 +10,11 @@
     import { requestJoinRoom } from "../stores/roomStore";
     import gameStore from "../stores/gameStore";
 
+    let maxRotationDeg = 20;
+    let centerDistancePx = 200;
+    let cardWidth = 100;
+    let cardHeight = 150;
+
     onMount(async () => {
         // TODO: check if already connected to room, currently its overwriting the session
         const params = new URLSearchParams(window.location.search);
@@ -51,7 +56,7 @@
     {#if $sessionStore.gameState == GameState.Lobby}
         <div>
             <!-- Lobby and player list -->
-            <Lobby />
+            <Lobby {cardWidth} {cardHeight} {centerDistancePx} {maxRotationDeg} />
         </div>
     {/if}
 
@@ -59,11 +64,11 @@
         <div class="size-full">
             {#if $gameStore.isLobbyOverlayShown}
                 <div class="absolute inset-0 z-10 bg-white/30 dark:bg-black/30 backdrop-blur-sm mt-24">
-                    <Lobby />
+                    <Lobby {cardWidth} {cardHeight} {centerDistancePx} {maxRotationDeg} />
                 </div>
             {/if}
             <!-- Running game -->
-            <Main />
+            <Main {cardWidth} {cardHeight} {centerDistancePx} {maxRotationDeg} />
         </div>
     {:else if $sessionStore.gameState == GameState.Ended}
         <EndScreen />
diff --git a/frontend/src/routes/_module.svelte b/frontend/src/routes/_module.svelte
index 1f27cd9..f46c237 100644
--- a/frontend/src/routes/_module.svelte
+++ b/frontend/src/routes/_module.svelte
@@ -65,7 +65,7 @@
 </header>
 
 <div class="main-container">
-    <div class="page-slot">
+    <div class="page-slot" style="overflow-y: auto;">
         <slot />
     </div>
 </div>
diff --git a/frontend/src/stores/cardDeck.ts b/frontend/src/stores/cardDeck.ts
new file mode 100644
index 0000000..659451d
--- /dev/null
+++ b/frontend/src/stores/cardDeck.ts
@@ -0,0 +1,13 @@
+import ClassicCard from "../components/Cards/ClassicCard.svelte";
+import HexV1Card from "../components/Cards/HexV1Card.svelte";
+
+interface CardDeck {
+    id: number;
+    name: string;
+    cardComponent: any;
+}
+
+export const CardDecks: CardDeck[] = [
+    { id: 0, name: "Classic", cardComponent: ClassicCard },
+    { id: 1, name: "HexV1", cardComponent: HexV1Card },
+];
diff --git a/frontend/src/stores/sessionStore.ts b/frontend/src/stores/sessionStore.ts
index 7c1a12e..809be5d 100644
--- a/frontend/src/stores/sessionStore.ts
+++ b/frontend/src/stores/sessionStore.ts
@@ -80,6 +80,10 @@ interface PlayedCardUpdateObj {
     Card: Card;
 }
 
+interface SetCardDeckReq {
+    CardDeckId: number;
+}
+
 interface PlayCardReq {
     CardIndex?: number;
     CardData: any;
@@ -367,6 +371,13 @@ class SessionManager {
         }
     }
 
+    setCardDeck(id: number) {
+        let request: SetCardDeckReq = {
+            CardDeckId: id,
+        };
+        this.sendMessage("SetCardDeck", JSON.stringify(request));
+    }
+
     drawCard() {
         this.sendMessage("DrawCard", "");
     }
diff --git a/frontend/src/views/Game/Lobby.svelte b/frontend/src/views/Game/Lobby.svelte
index 6d40839..cc00282 100644
--- a/frontend/src/views/Game/Lobby.svelte
+++ b/frontend/src/views/Game/Lobby.svelte
@@ -1,10 +1,12 @@
 <script lang="ts">
     import RenamePlayer from "../../components/RenamePlayer.svelte";
-    import { Table, TableBody, TableBodyCell, TableBodyRow, TableHead, TableHeadCell, TableSearch, Badge, Button, Modal, Popover, Tooltip } from "flowbite-svelte";
+    import CardDeckShowcase from "../../components/CardDeckShowcase.svelte";
+    import { Table, TableBody, TableBodyCell, TableBodyRow, TableHead, TableHeadCell, TableSearch, Badge, Button, Modal, Popover, Tooltip, Card } from "flowbite-svelte";
     import { CircleArrowOutUpLeft, Copy, AlertCircle, UserX, Play, TextCursorInput, Gamepad2 } from "lucide-svelte";
     import { _ } from "svelte-i18n";
     import { GameState, sessionStore } from "../../stores/sessionStore";
     import { toggleLobbyOverlay } from "../../stores/gameStore";
+    import { CardDecks } from "../../stores/cardDeck";
 
     let copied = false;
     let showLeaveModal = false;
@@ -16,6 +18,12 @@
     let showRenameModal = false;
     let kick_player = "";
     let showKickModal = false;
+    let showCardDeckModal = false;
+
+    export let maxRotationDeg: number;
+    export let centerDistancePx: number;
+    export let cardWidth: number;
+    export let cardHeight: number;
 
     function filteredPlayers() {
         return players.filter((player) => player.Username.toLowerCase().includes(searchQuery.toLowerCase()));
@@ -85,34 +93,61 @@
     </div>
 </Modal>
 
-<!-- Leave Room Button -->
-<Button
-    color="none"
-    class="sm:absolute m-2 border-2 border-gray-500 dark:border-gray-300 hover:bg-gray-500 dark:hover:bg-gray-300 hover:text-white dark:hover:text-black rounded-full text-gray-500 dark:text-gray-300"
-    on:click={() => {
-        showLeaveModal = true;
-    }}
->
-    <CircleArrowOutUpLeft class="mr-2" />
-    <span>{$_("lobby.leave_game")}</span>
-</Button>
+<!-- Modal: Select card deck -->
+<Modal bind:open={showCardDeckModal} size="md" backdropClass="fixed inset-0 z-40 bg-gray-900 bg-black/50 dark:bg-black/80 backdrop-opacity-50" style="color: unset;" autoclose outsideclose>
+    <div class="text-center">
+        <h3 class="mb-5 text-lg font-normal text-gray-500 dark:text-gray-400">
+            {$_("lobby.card_deck_modal")}
+        </h3>
+        <div class="grid justify-center gap-5">
+            {#each CardDecks as cardDeck}
+                <Card style="color: unset;">
+                    <span class="mb-[-15px] text-xl">{cardDeck.name}</span>
+                    <div class="flex justify-center">
+                        <CardDeckShowcase cardComponent={cardDeck.cardComponent} cardDeckId={cardDeck.id} {cardHeight} {cardWidth} centerDistancePx={centerDistancePx * 3} {maxRotationDeg} />
+                    </div>
+                    <Button
+                        on:click={() => {
+                            sessionStore.setCardDeck(cardDeck.id);
+                        }}>{$_("lobby.choose_card_deck")}</Button
+                    >
+                </Card>
+            {/each}
+        </div>
+        <Button on:click={() => (showCardDeckModal = false)} color="alternative" class="mt-5 hover:text-dark hover:bg-gray-100">{$_("lobby.cancel")}</Button>
+    </div>
+</Modal>
 
-<!-- Return to game Button -->
-{#if sessionStore.getState().gameState !== GameState.Lobby}
+<div class="flex">
+    <!-- Leave Room Button -->
     <Button
         color="none"
-        class="sm:absolute m-2 right-0 border-2 border-gray-500 dark:border-gray-300 hover:bg-gray-500 dark:hover:bg-gray-300 hover:text-white dark:hover:text-black rounded-full text-gray-500 dark:text-gray-300"
+        class="m-2 border-2 border-gray-500 dark:border-gray-300 hover:bg-gray-500 dark:hover:bg-gray-300 hover:text-white dark:hover:text-black rounded-full text-gray-500 dark:text-gray-300"
         on:click={() => {
-            toggleLobbyOverlay();
+            showLeaveModal = true;
         }}
     >
-        <span>{$_("lobby.return_to_game")}</span>
-        <Gamepad2 class="ml-2" />
+        <CircleArrowOutUpLeft class="mr-2" />
+        <span>{$_("lobby.leave_game")}</span>
     </Button>
-{/if}
+
+    <!-- Return to game Button -->
+    {#if sessionStore.getState().gameState !== GameState.Lobby}
+        <Button
+            color="none"
+            class="m-2 ml-auto border-2 border-gray-500 dark:border-gray-300 hover:bg-gray-500 dark:hover:bg-gray-300 hover:text-white dark:hover:text-black rounded-full text-gray-500 dark:text-gray-300"
+            on:click={() => {
+                toggleLobbyOverlay();
+            }}
+        >
+            <span>{$_("lobby.return_to_game")}</span>
+            <Gamepad2 class="ml-2" />
+        </Button>
+    {/if}
+</div>
 
 <!-- Game Status -->
-<div class="text-center p-6 w-full">
+<div class="md:mt-[-65px] text-center p-6 w-full">
     <span
         >{$_("game_status.game_status")}
         <Badge color="dark">
@@ -199,6 +234,29 @@
     <TableSearch bind:inputValue={searchQuery} placeholder={$_("lobby.search_player")} />
 {/if}
 
+<!-- Card deck selection -->
+{#if sessionStore.getState().gameState == GameState.Lobby}
+    <div class="flex w-full justify-center my-10">
+        <Card style="color: unset;">
+            <span class="text-xl">{$_("lobby.selected_card_deck")}</span>
+            <span class="opacity-80 mb-[-15px]">{CardDecks.find((e) => e.id == $sessionStore.cardDeckId)?.name}</span>
+            <div class="flex justify-center">
+                <CardDeckShowcase
+                    cardComponent={CardDecks.find((e) => e.id == $sessionStore.cardDeckId)?.cardComponent}
+                    cardDeckId={CardDecks.find((e) => e.id == $sessionStore.cardDeckId)?.id ?? 0}
+                    {cardHeight}
+                    {cardWidth}
+                    centerDistancePx={centerDistancePx * 3}
+                    {maxRotationDeg}
+                />
+            </div>
+            {#if sessionStore.getPlayerPermissions().isHost}
+                <Button on:click={() => (showCardDeckModal = true)}>{$_("lobby.change_card_deck")}</Button>
+            {/if}
+        </Card>
+    </div>
+{/if}
+
 <!-- Players Table -->
 <Table striped hoverable noborder class="mb-16">
     <TableHead>
diff --git a/frontend/src/views/Game/Main.svelte b/frontend/src/views/Game/Main.svelte
index 828279a..c91f8e5 100644
--- a/frontend/src/views/Game/Main.svelte
+++ b/frontend/src/views/Game/Main.svelte
@@ -1,17 +1,16 @@
 <script lang="ts">
     import type { PlayerObj } from "../../stores/sessionStore";
     import { derived, get } from "svelte/store";
-    import ClassicCard from "../../components/Cards/ClassicCard.svelte";
     import CardDisplay from "../../components/Game/CardDisplay.svelte";
     import { sessionStore } from "../../stores/sessionStore";
     import OpponentDisplay from "../../components/Game/OpponentDisplay.svelte";
-    import HexV1Card from "../../components/Cards/HexV1Card.svelte";
+    import { CardDecks } from "../../stores/cardDeck";
 
-    let maxRotationDeg = 20;
-    let centerDistancePx = 200;
-    let cardWidth = 100;
-    let cardHeight = 150;
-    let cardComponent = [ClassicCard, HexV1Card][$sessionStore.cardDeckId ?? 0];
+    export let maxRotationDeg: number;
+    export let centerDistancePx: number;
+    export let cardWidth: number;
+    export let cardHeight: number;
+    let cardComponent = CardDecks.find((e) => e.id == $sessionStore.cardDeckId)?.cardComponent;
 
     let opponents = derived(sessionStore.store, ($store) => $store.players.filter((e) => e.PlayerId != sessionStore.getUserId()));
     let playerActive = derived(sessionStore.store, ($store) => ($store.playerStates[$store.userId ?? ""] ?? "").Active ?? false);