Play the maps you already beat on a higher difficulty or play scramble. Scramble probably has the best return rate once you've got a good set of traps you can rely on but it's more time consuming.

play the 1º map on easy

Make sure you don't take damage. You get 2 skulls for untouchable.

perfect 1
untouchable 2
more faster 1
more combo 1
do slowly all
after go on map 2 map 3

If you are having trouble on a map, you could lower the difficulty to clear it once and then try again on your current difficulty. But for farming, the first map on Apprentice is the fastest way to farm skulls, just be sure to get perfect bonus when you do it.

start doing the map on easiest difficulty to earn 5 skulls + bonus skulls on first time beating them on apprentice. then again on warmage difficulty to get up to 5 skulls +bonus skulls.

Originally posted by kousa.kai:

play the 1º map on easy

3rd map has more enemies, a good central kill lane, and no Orc Archers.

It's best for grinding Skulls and trap/weapon upgrades (which need a lot of kills - you'll have to run the first map 3 times to get as many kills as you get on one run on the third map).

Play all maps on easy... do not take damage and beat par time... it is the fastest way

Thanks everyone. :D
I ended up doing scramble. But, I might go back and redo all the levels on easy now I've beaten the main campaign to unlock everything else and upgrade them. :D

Originally posted by Cougarific:

Originally posted by kousa.kai:

play the 1º map on easy

3rd map has more enemies, a good central kill lane, and no Orc Archers.

It's best for grinding Skulls and trap/weapon upgrades (which need a lot of kills - you'll have to run the first map 3 times to get as many kills as you get on one run on the third map).

Ty so much! This map is really easy too and Im getting more skull than map 1