itch.io

Dont waste resources in the beginning, destroy the catapults first, use the suck skill to quickly get rid of the first 2  big waves, then play normally. Also use tanky cheap units like the centaur

its quite rare. You can hover over the enemies to see what they drop, before starting a level. Look for a level that has lots of those sandbag builders that you can farm on a higher difficulty.

I was pretty much stuck there until the recent patches nerfed some enemy units.  
Waiting out the   first big wave with almost full resources and  using the suck skill to get rid of them quickly worked for me in the end. After that play as normal and focus  the cannons.

catapults and paladins, the hammer guys, pretty much oneshot most units. there are a few units that need some adjustments. I get absolutely destroyed on 3-12. Like no chance at all at winning it.