Sender Unknown is a special event stage. Upon first completion, it grants the player a random gift.
This stage is extremely easy. The boss, Package Doge, is extremely weak, dealing very little damage and not moving whatsoever, despite being a dreaded Metal-type enemy. Just send out fast attackers like Cow Cat and Crazed Cow to quickly kill it. The base will fall just as quickly.
For an even faster clear, just use an AoE Long Distance unit like Kite who will attack the boss but end up hitting the base, winning the level very quickly.
But the best way to clear this stage, is sending some critical hitter units, because, as previously mentioned, the boss is a Metal enemy.
- This stage has a reloading time for gifts, you wont get any gifts after first play, you need to wait till it refreshes.
- This stage has the lowest base HP in the entire game.