diff --git a/src/core/configuration/DefaultConfig.ts b/src/core/configuration/DefaultConfig.ts
index 44875c2c8..5fd401740 100644
--- a/src/core/configuration/DefaultConfig.ts
+++ b/src/core/configuration/DefaultConfig.ts
@@ -36,7 +36,7 @@ export class DefaultConfig implements Config {
                 }
             case UnitType.Shell:
                 return {
-                    cost: (p: Player) => (p.units(UnitType.Destroyer).length + 1) * 500_000,
+                    cost: (p: Player) => 0,
                     territoryBound: false
                 }
             case UnitType.Port:
diff --git a/src/core/configuration/DevConfig.ts b/src/core/configuration/DevConfig.ts
index dca20c927..ce09d8320 100644
--- a/src/core/configuration/DevConfig.ts
+++ b/src/core/configuration/DevConfig.ts
@@ -5,7 +5,7 @@ export const devConfig = new class extends DefaultConfig {
     unitInfo(type: UnitType): UnitInfo {
         const info = super.unitInfo(type)
         const oldCost = info.cost
-        info.cost = (p: Player) => 0 * oldCost(p) / 10000
+        info.cost = (p: Player) => oldCost(p) / 10
         return info
     }
 
diff --git a/src/core/game/PlayerImpl.ts b/src/core/game/PlayerImpl.ts
index 05c98b08c..dc3e82874 100644
--- a/src/core/game/PlayerImpl.ts
+++ b/src/core/game/PlayerImpl.ts
@@ -278,6 +278,9 @@ export class PlayerImpl implements MutablePlayer {
     }
 
     removeGold(toRemove: Gold): void {
+        if (toRemove > this._gold) {
+            throw Error(`Player ${this} does not enough gold (${toRemove} vs ${this._gold}))`)
+        }
         this._gold -= toRemove
     }