What else do I need?Baron Geddon?
What legendaries are must have?
You have the ones that are needed (some don't even use Cairne because he's too slow).
The rest is up to you. You adapt to what you are facing. Ysera if you face a lot of control, The Black Knight for big taunts, Harisson for weapons, Deathwing if you often get in topdeck situation lategame, Sylvana, etc.
What I am finding is that with a little change out for taunt you can hold off the zoo, and then baron will either clear it or take one of the nukes, saving your big threats from them.
But that's just what I am experiencing at my current level.
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