I`m not sure about Giants. Ad attack and giant retaliate, then earthquaqe ad no retaliation, then attack for attack, then first round again, so in 4 rounds ad hit 6 times, and giant 6 times hit, +2 no retaliation from close range. Not sure for ecsact numbers, but i think close call. giant have more % crit, ad can get maybe 1 crit in those 4 rounds, but giant will have 1 for sure. And 134 more Hp on giant side.
But i think you all forgot real winner in this compettition : Troll. Of course if battle played at night or underground