With a L2 Monster Lab, you should be able to fuse monsters together, making different creatures entirely. Like the Octo-Bolt, which has the looting power of a bolt, and the health of an Octo-ooze. It can still teleport.
I think that at Catapult level 4, you should be able to launch Goo, which creates more monsters for support. A Small Load makes 20 pokeys, Medium brings 5 Ichis, Large builds one D.A.V.E, and Huge makes a level 1 Champion of your choice.
I think that when a Monster comes in contact with Goo (Factories, Hatcheries), then they get GR (Goo Rage), which doubles their damage and speed for 10 seconds.
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