Cheerios (Odd Hero Power Mage)

The three top performing cards for me are Daring Fire-Eater, Stonehill Defender and Arcane Tyrant.

Daring Fire-Eater makes your hero power do extra damage to kill an opposing Stonehill, or to just hit face (4Head). Since we wanna do as much damage with the hero power as we can, this is the best way to do so.

Stonehill Defender makes a body that makes another body. These bodies usually are dummy thicc so we can play them on the board and our opponent will need to either attack into them with smaller dudes or use removal.

Arcane Tyrant is such a tempo swing after using a board clear. One of my favorite plays to do is use a Dragon's Fury, wrath the board for 5 damage, and then instantly put out 10/12 of stats with two Arcane Tyrant and a Fire Fly on turn 7. It's so fun and if you were behind before that play, you just turn the whole match on it's head for 7 mana. 

Aggro is a fairly easy matchup to mulligan against. 

Stonehill gives two bodies to defend your face from SMOrcing.

Tar Creeper will force uneven trades from the opponent.

Pyromaniac gives you cards for each HP kill you get, which is what we wanna do anyway.

Blast Wave is good against a opponent that wants to flood the board with small dudes, like Paladin.

Control v Control is one of the more fun matchups in my opinion, though there isn't much I'd say to mulligan for. You can make an argument for Voodoo Doll, but you have to make them count, and you don't need them in the early game, so there's no reason to dig for it.

Black Cat is card draw on a 3/3, including spell damage, which doesn't usually apply, but it can in specific circumstances. 

Astromancer is always good in the extended matches where you hit those later turns and have a ton of cards in your hand, a turn 7 Astromancer is a threat to deal with that the other control deck will want to use their removal on, protecting your Jan'alai that much more.