I don't think Arcblade is particularly OP, but it's easily the least skilled of all the abilities. Ability skill list, most skilled to least skilled, descending order, goes something like, Titan bubble of love, still have to fight despite placing it and keep yourself about you. Warlock sunsinger, still susceptible to being shot, only provides buff, have to use well. Golden Gun, no extra ability to take damage, only three shots, have to use them well. Fist of Havoc, very situational, depends how you use it. Nova Bomb, again, fairly situation, have to aim it correctly, little skill required. Arcblade, mash buttons skate across map. I don't think Arcblade is OP, if anything, used correctly, the bubble of life is the most OP, but it's clearly the least skilled.