Here is the full list of all 13 Siegecraft Commander (EU) trophies - there are 1 bronze, 11 gold and 1 platinum.
Obtained all trophies in Siegecraft Commander!
Hit 10 enemy units with the Freeze spell
Hit 8 friendly units with the Haste spell
Caught a cow with a dragon
Destroyed 10 units with a single TNT
Chained 4 towers with a single Hex Curse
Changed a cow into a mad cow
Get 5 tower kills by destroying the tower it is linked to
As a tower is being destroyed, fire a projectile and destroy an enemy tower
Destroyed a tower with a building projectile
Killed a tower with a full power trebuchet shot
Shot down an air unit with a TNT
Crashed air units into each other