Mulligans
Combo Mulligans
You always mulligan for Call to Arms and card draw.
Against Combo decks like Malygosdruid, keep 1x Dirty Rat, wait for a good moment, most likely after your opponent has drawn a bunch of cards and then drop your Rat and kill what you pull.
Against slow decks with low pressure, you can keep Utheror some parts of your combo to finish the game fast.
Paladin
Combo preparation
1.) Play Uther of the Ebon Blade.
2.) You need Emperor Thaurissan, Auctionmaster Beardo and 3x random spells which cost (1) or less mana.
3.) Drop Emperor Thaurissan, when you be sure that you have Auctionmaster Beardo and 3x random spells which cost (1) or less mana in your hand.
4.) !!! Make sure you have enough space on your board to drop Emperor and 4 Horseriders !!!
Use your hero power => play Auctionmaster Beardo => play a spell => use hero power => play a spell => use hero power => play a spell => use hero power => Justice demands retribution and win the game.