The King is Watching achievements

Kill your first enemy

Achieve victory for the first time

Get rid of all the trees on a level

Have at least one unit of every class on the battlefield at once

Have 40 units on the battlefield at once

Reach +100% damage for any unit class

Beat each boss of the Graveyard

Execute a total of 200 of your own units

Achieve victory on Threat level 3

Achieve victory on Threat level 5

Beat a level without taking any castle damage

Achieve victory on Threat level 9