This level is very easy with fast attackers. Take cheap and fast cats: Lion, Manic Lion, Manic Wall, Express Cat, and Awakened Bahamut are good candidates. Spam Lions immediately as you save up for Awakened Bahamut. Then send Manic Walls and lions until the base is destroyed. Tackey will shoot over the heads of your attackers, and they should be able to destroy the base quickly.