I tried this on easy after accumulating a tons of money with banana bank.

The key here is you use monkey temple.

How would you use it?

Well, you sacrifice 30k worth of cannon, 30k worth of ice, 30k worth of glue, 30k worth of wizard.

Some says you got to put some mortar too in exchange of some of the cannons. Make sure the upgrade of the sacrifices vary.

Please correct me if I am wrong.

Now, the temples will shoot rockets. The rockets hit ZOMG really hard. In fact, at the end levels, (150+), those 4 temples are the only one remotely cost effective against ZOMG.

I played till level 150. Nothing else works.

I've heard snipper can take out zomg in 20 hits. Don't know that. Without splash damage, they can't kill infinite numbers of zomg.