diff --git a/src/BoosterFactory.ts b/src/BoosterFactory.ts
index f3708cf59..c8b662907 100644
--- a/src/BoosterFactory.ts
+++ b/src/BoosterFactory.ts
@@ -48,10 +48,10 @@ class ColorBalancedSlotCache {
 
 	constructor(cardPool: CardPool, options: Options = {}) {
 		const localGetCard = options.getCard ?? getCard;
-		for (const cid of cardPool.keys()) {
+		for (const [cid, count] of cardPool) {
 			if (!(localGetCard(cid).colors.join() in this.byColor))
 				this.byColor[localGetCard(cid).colors.join()] = new CardPool();
-			this.byColor[localGetCard(cid).colors.join()].set(cid, cardPool.get(cid) as number);
+			this.byColor[localGetCard(cid).colors.join()].set(cid, count);
 		}
 
 		this.monocolored = new CardPool();
@@ -242,9 +242,9 @@ function filterCardPool(slotedCardPool: SlotedCardPool, predicate: (cid: CardID)
 	for (const slot in slotedCardPool) {
 		specialCards[slot] = new CardPool();
 		filteredCardPool[slot] = new CardPool();
-		for (const cid of slotedCardPool[slot].keys()) {
-			if (predicate(cid)) specialCards[slot].set(cid, slotedCardPool[slot].get(cid) as number);
-			else filteredCardPool[slot].set(cid, slotedCardPool[slot].get(cid) as number);
+		for (const [cid, count] of slotedCardPool[slot]) {
+			if (predicate(cid)) specialCards[slot].set(cid, count);
+			else filteredCardPool[slot].set(cid, count);
 		}
 	}
 	return [specialCards, filteredCardPool];
@@ -532,13 +532,13 @@ class STXBoosterFactory extends BoosterFactory {
 		// Filter STA cards according to session collections
 		if (options.session && !options.session.unrestrictedCardPool()) {
 			const STACards: CardPool = options.session.restrictedCollection(["sta"]);
-			for (const cid of STACards.keys()) {
+			for (const [cid, count] of STACards) {
 				const card = getCard(cid);
 				// Remove Japanese versions
 				if (parseInt(card.collector_number) <= 63)
 					this.mysticalArchiveByRarity[card.rarity].set(
 						cid,
-						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, STACards.get(cid) as number)
+						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, count)
 					);
 			}
 		} else {
@@ -1012,10 +1012,10 @@ class YDMUBoosterFactory extends BoosterFactory {
 		if (options.session && !options.session.unrestrictedCardPool()) {
 			const YDMUCards: CardPool = options.session.restrictedCollection(["ydmu"]);
 			this.alchemyCards = { uncommon: new CardPool(), rare: new CardPool(), mythic: new CardPool() };
-			for (const cid of YDMUCards.keys())
+			for (const [cid, count] of YDMUCards)
 				this.alchemyCards[getCard(cid).rarity].set(
 					cid,
-					Math.min(options.maxDuplicates?.[getCard(cid).rarity] ?? 99, YDMUCards.get(cid) as number)
+					Math.min(options.maxDuplicates?.[getCard(cid).rarity] ?? 99, count)
 				);
 		} else {
 			this.alchemyCards = { uncommon: new CardPool(), rare: new CardPool(), mythic: new CardPool() };
@@ -1150,12 +1150,12 @@ class BROBoosterFactory extends BoosterFactory {
 
 		if (options.session && !options.session.unrestrictedCardPool()) {
 			const BRRCards: CardPool = options.session.restrictedCollection(["brr"]);
-			for (const cid of BRRCards.keys()) {
+			for (const [cid, count] of BRRCards) {
 				const card = getCard(cid);
 				if (parseInt(card.collector_number) <= 63)
 					this.retroArtifacts[card.rarity].set(
 						cid,
-						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, BRRCards.get(cid) as number)
+						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, count)
 					);
 			}
 		} else {
@@ -1391,12 +1391,12 @@ class MOMBoosterFactory extends BoosterFactory {
 
 		if (options.session && !options.session.unrestrictedCardPool()) {
 			const MULCards: CardPool = options.session.restrictedCollection(["mul"]);
-			for (const cid of MULCards.keys()) {
+			for (const [cid, count] of MULCards) {
 				const card = getCard(cid);
 				if (parseInt(card.collector_number) <= 65)
 					this.multiverseLegend[card.rarity].set(
 						cid,
-						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, MULCards.get(cid) as number)
+						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, count)
 					);
 			}
 		} else {
@@ -1626,13 +1626,10 @@ class WOEBoosterFactory extends BoosterFactory {
 		super(cardPool, landSlot, options);
 		if (options.session && !options.session.unrestrictedCardPool()) {
 			const WOTCards: CardPool = options.session.restrictedCollection(["wot"]);
-			for (const cid of WOTCards.keys()) {
+			for (const [cid, count] of WOTCards) {
 				const card = getCard(cid);
 				if (parseInt(card.collector_number) <= WOEBoosterFactory.MaxWOTCollectorNumber)
-					this.wotPool[card.rarity].set(
-						cid,
-						Math.min(options.maxDuplicates?.[card.rarity] ?? 99, WOTCards.get(cid) as number)
-					);
+					this.wotPool[card.rarity].set(cid, Math.min(options.maxDuplicates?.[card.rarity] ?? 99, count));
 			}
 		} else {
 			for (const cid of CardsBySet["wot"]) {
diff --git a/src/Session.ts b/src/Session.ts
index 814827d20..f7d2357cf 100644
--- a/src/Session.ts
+++ b/src/Session.ts
@@ -532,7 +532,7 @@ export class Session implements IIndexable {
 			for (const s of sets)
 				if (s in CardsBySet)
 					for (const cid of CardsBySet[s].filter((cid) => cardPool.has(cid)))
-						restricted.set(cid, cardPool.get(cid) as number);
+						restricted.set(cid, cardPool.get(cid)!);
 				else console.error(`Session.restrictedCollection Error: '${s}' not in CardsBySet.`);
 			return restricted;
 		} else return cardPool;
@@ -561,13 +561,10 @@ export class Session implements IIndexable {
 
 		// Compute the minimum count of each remaining card
 		for (const c of intersection) {
-			collection.set(c, useCollection[0] ? (Connections[user_list[0]].collection.get(c) as number) : 4);
+			collection.set(c, useCollection[0] ? Connections[user_list[0]].collection.get(c)! : 4);
 			for (let i = 1; i < user_list.length; ++i)
 				if (useCollection[i])
-					collection.set(
-						c,
-						Math.min(collection.get(c) as number, Connections[user_list[i]].collection.get(c) as number)
-					);
+					collection.set(c, Math.min(collection.get(c)!, Connections[user_list[i]].collection.get(c)!));
 		}
 		return collection;
 	}
@@ -920,10 +917,10 @@ export class Session implements IIndexable {
 
 		// Add a new card to skipped pile. (Make sure there's enough cards for the player to draw if this is the last pile)
 		if (s.cardPool.length > 1 || (s.currentPile < 2 && s.cardPool.length > 0))
-			s.piles[s.currentPile].push(s.cardPool.pop() as UniqueCard);
+			s.piles[s.currentPile].push(s.cardPool.pop()!);
 		// Give a random card from the card pool if this was the last pile
 		if (s.currentPile === 2) {
-			const card = s.cardPool.pop() as UniqueCard;
+			const card = s.cardPool.pop()!;
 			Connections[s.currentPlayer()].pickedCards.main.push(card);
 			Connections[s.currentPlayer()].socket.emit("winstonDraftRandomCard", card);
 			this.draftLog?.users[s.currentPlayer()].picks.push({
@@ -948,7 +945,7 @@ export class Session implements IIndexable {
 			piles: [...s.piles.map((p, idx) => p.slice(0, idx < s.currentPile ? -1 : undefined).map((c) => c.id))],
 		});
 		Connections[s.currentPlayer()].pickedCards.main.push(...s.piles[s.currentPile]);
-		if (s.cardPool.length > 0) s.piles[s.currentPile] = [s.cardPool.pop() as UniqueCard];
+		if (s.cardPool.length > 0) s.piles[s.currentPile] = [s.cardPool.pop()!];
 		else s.piles[s.currentPile] = [];
 		this.winstonNextRound();
 		return true;
@@ -1250,8 +1247,8 @@ export class Session implements IIndexable {
 			//                       Column           Row
 			const idx = choice < 3 ? 3 * i + choice : 3 * (choice - 3) + i;
 			if (s.boosters[0][idx] !== null) {
-				Connections[s.currentPlayer()].pickedCards.main.push(s.boosters[0][idx] as UniqueCard);
-				pickedCards.push(s.boosters[0][idx] as UniqueCard);
+				Connections[s.currentPlayer()].pickedCards.main.push(s.boosters[0][idx]!);
+				pickedCards.push(s.boosters[0][idx]!);
 				log.pick.push(idx);
 				s.boosters[0][idx] = null;
 			}
diff --git a/src/cardUtils.ts b/src/cardUtils.ts
index c46ad86de..2f289b0c2 100644
--- a/src/cardUtils.ts
+++ b/src/cardUtils.ts
@@ -58,7 +58,7 @@ export function pickCard(
 			);
 			if (candidates.length > 0) {
 				const tmpPool = new CardPool();
-				for (const cid of candidates) tmpPool.set(cid, cardPool.get(cid) as number);
+				for (const cid of candidates) tmpPool.set(cid, cardPool.get(cid)!);
 				cid = randomFunc(tmpPool);
 			}
 		}