Oblivion

Oblivion is a rare Necrobinder skill costing 0 Energy that makes every card you play this turn apply 3 Doom to the enemy. This transforms an entire turn's worth of card plays into Doom stacking, and since it costs nothing, it doesn't reduce the number of cards you can chain afterward.

Oblivion is devastating when combined with Neurosurge for extra Energy and draws, allowing more card plays in the Doom-stacking turn. Borrowed Time provides additional Energy, and Wisp adds free Energy while counting as another Doom trigger. Follow up with Time's Up on a subsequent turn to convert all that Doom into lethal damage.

In Necrobinder Doom builds, Oblivion turns high-card-count turns into massive Doom spikes. Against multi-phase bosses like Test Subject #C10, a single Oblivion turn with 6-7 card plays can apply 18-21 Doom in one shot. Pair with Shroud to also gain Block for every Doom application, turning an explosive offensive turn into a well-defended one.