Jack

I think O.S.C.A.R. Is a wonderfully designed and poorly executed Elite. His health bar is way too chunky to have invulnerability phases like he does, and the traps on the map don't even help kill him most of the time. He's so wonderfully designed but the only option they leave you to dealing with him is to run away and avoid him... Which I think makes for a horrible choice to such an interesting enemy.