If Sauron, the Necromancer leaves the battlefield before the delayed triggered ability resolves, that ability will exile the token, even if Sauron, the Necromancer later returns to the battlefield or you control another copy of Sauron, the Necromancer as your Ring-bearer
The power issue here is pronounced in Pioneer, which is built on a clear era split between Mana Leak being in Standard and it not being there
To do that, the cards needed to be firmly and consistently rooted in the setting, so there was no question that we understood and appreciated Warhammer
As with any cards with two effects that have synergy, the design space for this mechanic is limited
Compared to the sword, it's cheaper, you dig twice as deep, and if your deck likes discard synergies then you get to pitch the exact card you need
The other deck is still very slow, but has a reliable way to convert our advantage into a win once it gets rolling