dominion of 5 and In a solid dominon he’ll have over 300 hitpoints --> means probably not usuable for expansion against any opponent.
but to be honest even though you say he's still usable late in teh game you don't base your strat around him anymore so it's not really a problem.. he's just not THAT good as you make it sound there IMHO 
 
I don't know his slots but how would you kit him out?
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