WIth so much druid, hunter and sometimes warrior in the meta, the Skulking Geist is reaaally good. Not only destroy their removal but also their combos sometimes (Like Play Dead, Naturalize [/card]or [card]Dark Pact thier minions to avoid Hex, The Soularium/Soulfire, etc)
The Black Knight is a tech against 8+mana taunts which almost all classes run at least one (mainly The Lich King), but you profit a lot even against a Tar Creeper. The tempo it gains and the fact of being a Classic Legendary useful in most metas make it really worth of crafting (Sometimes is like a prenerf Big Game Hunter but better).
The Spellbreaker as a replacement will be useful but only if you have pressured face enough by turn 8. If not, thier 8/8 silenced taunt can still punish you. (I also run 2 Hex which is the best against resurrection mechanics but not as good as spellbreaker for going face as Hex still summon a taunt for them).
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