I run encouraged and oblivion shield. cheaper, plus you can rack up damage anyways so it works out well with his summons
I think Oblivion shield is the clear better option over either OWN or Vapo, because it actually consumes opposing resources, rather than restricting opposing options. That's a big deal. Vapo and OWN don't eat your opponents attacks, they just stop them from attacking. But, if a player wants to attack an O Shield champ, they must get through O Shield first by spending AP. For any tank, especially one which can survive multiple rounds for multiple O Shield triggers, O Shield is the clear winner. Vapo and OWN are better on squishy or melee champions that would otherwise have a hard time surviving a round, and need to do so. As for U1, Dictate or Encouraged seem like better choices than Logistics, because those two abilities improve damage. The exact choice probably depends upon the deck. Here's how I ultimately think about the upgrades: +DMG [Encouraged/Dictate] / no DMG [Logistics] Prevention [O Shield] / Restriction [Vapo/OWN]
Kalasle's analysis on U2 is sound; I'd definitely go Oblivion Shield there, and also take Encouraged. The permanent damage from Dictate would favor a stall-oriented attrition deck that gives it time to stack up. Encouraged is the superior choice in decks that like to swarm and spam meat, granting you huge bonus damage nearly every turn. Right now I'm running him in the latter deck, and he's never been a bad deploy.
