this is a guide about the cards you gain beating the caves of trial:
cave 1:lord of fire (or devil),who is the red titan
cave 2:blue dragon,who is the blue titan
cave 3:earth dragon (or diablo),who is the green titan
cave 4:lord of shadows,who is the purple titan
cave 5:bezerker,which is a skill card
Just a tip for a good army:use the green hero.
Equip:dragon rider,centaur,black knight,frost giant(or yetti,its the same unit),succubus,fire demon or devil(the red titan),comet shoot,rain of arrows,healing wave,phoenix strike and lighting bolt or freeze trap(its better to equip the lighting bolt)
STRATEGY:set up your units in the castle(front row:dragon rider,black knight,frost giant and the titan.back row:centaur and succubus).Use comet shoot when ranged units attack you and use rain of arrows to clear the battlefield.Use the first phoenix strike to kill all the opponent units and then,use the phoenix strikes to counter the revenge waves.Same with the lighting bolt or freeze trap.Use the healing wave to heal your units after a revenge wave.
DO NOT ATTACK until you have got all your units ready(its better to attack in groups),and kill the enemy hero near your castle(lure him by using comet shoot on him)
Will do! :D