The Librarian (Promo)

Your attacks with stealth get "When this chain link resolves, banish all action cards defending this." Instant -- {c}{c}{c}: Look at the top card of an opposing hero's deck. If it's blue, you may banish it. Until end of turn, you may play blue cards from that hero's banished zone without paying their {r} cost.

Mentor (You may only have Minerva in your deck if your hero is young.) At the start of your turn, if Minerva is face down in your arsenal, you may turn her face up. 1H weapons you control have +1 [Power]. Whenever a weapon you control hits, put a lesson counter on Minerva. Then if there are 3 or more lesson counters on Minerva, banish her, search your deck a specialization card, put it face up into your arsenal, and shuffle your deck.

The first time each turn you create a Gold token from an effect you control, draw a card. The first time each turn you would fail to win a clash, instead you may destroy a Gold you control. If you do, put 1 of the revealed cards on the bottom of its owner's deck, then clash again.

Mentor (You may only have Sutcliffe in your deck if your hero is young.) At the start of your turn, if Sutcliffe is face down in your arsenal, you may turn him face up. Whenever you play a 'non-attack' action card, deal 1 arcane damage to each hero and put a lesson counter on Sutcliffe for each damage dealt this way. Then if there are 3 or more lesson counters on Sutcliffe, banish him, search your deck a specialization card, put it face up into your arsenal, and shuffle your deck.