how to beat colossus: have white tiger, death, goblin, centaurion, hell raider and paladins maxed out. equip all with platinum sword, hercules grip to centaurion if you have it.
In battle: wait for the tiger and death to finish and then press c and the forword button. Cast rage everytime it runs out until the colossus appears. Then just keep waiting for a meteor 2 and cast it on him until he dies, he should approach quite a screen distance from your hero but that's ok. He'll die soon enough
Few tips:
When the counter attack are too great for you to keep attacking, retreat and use rain of arrows.
At the castle there's a line of strong defense. Use meteor to pick on them one by one so that they charge. When you officially attack there will be no defenders except the zombies and goblins and engineers.
you should do the sidequests first, after doing it enter the battle, try to summon the tarots that can soulburst attack, stay out of enemies range. next turn soul burst all tarot and you win:D
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