Weavile from Plasma Freeze (#66) has a great spread attack and a great backup attack
Theres a shot that shell end up in some sort of Standard deck Boros Angels was a thing last year, remember but even if that doesnt happen, casual demand should be strong enough to keep her above $5
Gadrak isnt a super popular commander by any means, but Chriss deck offered something funky and fresh at the table, especially when it came to card interactions
Respond to the ETB trigger with [[Demonic Consultation]] ([[symbol:b]]) or [[Tainted Pact]] ([[symbol:1]] [[symbol:b]])
Not only that, but you can use Ulamog to destroy their best permanent before that, making the decision of what to sac even harder
It may cost seven to cast, but its well worth the price