Build Description
Pre-Wave: Place all but Fireball Towers at Markers 2 & 3
Step 1: Wait till Sharken is killed at Marker 1, collect its mana
Step 2: Place Fireball Tower at Marker 2 to kill another Sharken
Step 3: Spam Fireball and Magic Missile Towers around Marker 3 to kite and kill Ogre
Post-Wave: Swap to desired Hero and collect Mana Chests