How to defeat colossus : Put wizard, succubus, witch , goblin and any two titans of ur choice.{ try to put more powerful ones like dragon, white tiger, angel,}Put ring of strike accesory for ur titan if they are normal or weak in strike defence.
some cool accesories: turtle shield - sons and brothers reunion, super robo suit - end of hope, hercules grip - go go power goblins, flaming chariot - primal beast, ice rune - the colossus
anyone havin trouble with undying primal use ur wall creating ability of any unit to put a wall on the place where he is standing. then create fire or ice towers behind him. the wall will not get destroyed by the undying primal. i assure u.
THe black Goblins are awesome but there is a little drawback to it. They are not effected by our attacks. only non elemental works on them, what i mean to say is that when the succubus uses a flame wave it resists the attack. but you could make it fly or when the valkyire attacks him u cud stun him no need to give damage but just stun him.