diff --git a/src/core/execution/AttackExecution.ts b/src/core/execution/AttackExecution.ts
index 42d361736..daf17d759 100644
--- a/src/core/execution/AttackExecution.ts
+++ b/src/core/execution/AttackExecution.ts
@@ -120,6 +120,9 @@ export class AttackExecution implements Execution {
       new Set<TileRef>(),
     );
 
+    const penalty = Math.floor(this._owner.population() * 0.01);
+    this._owner.removeTroops(penalty);
+
     if (this.sourceTile !== null) {
       this.addNeighbors(this.sourceTile);
     } else {