Regression

Brings plot back 1 level but retains all its current stats and effects.

How players use it

King of Time Warper plan (Vao): level a Warper fast. Regression lowers a level but keeps its stats, so the plot can level again. Since 1.0 it cannot target level-1 plots. Rewind replays your last cards. With Brutal (+1 Adrenaline stack) Vao’s Warper summons almost continuously, and Farms raise Warper count; Vao stops at 200 to 300 to avoid crashes.
Regression, Rewind and Temp Null Regression lowers a plot by 1 level but keeps all its stats and effects, so the plot can be upgraded again for more stats. Since 1.0 it cannot target a level-1 plot. Debris (1.0) gives a Temp Null for each Regression.
Balance changes in 1.0 Regression can no longer target a level-1 plot. Broken plots are level 1.

In the King of Time's 9-card deck: a run as this king can start with it, and losing a battle offers cards from your own deck.
Loot after beating the King of Time in battle when that king is one of your enemies.
Merchant: Jack of Magic (tomes and enchantments).
Joker mode: pick it for a custom deck.

Entry	Effect
Debris King of Time decree	Whenever you use Regression, you get +1 Temp Null card.

Patch #24 2026-05-25
Ingenious perk (Universal): now gives you +3 levels instead of +5. This is long due, given we now have Regression and a buffed Patronage.
Patch #26 2026-05-30
Regression now works with Broken Cabulators and Broken Gachas!
1.0 2026-11-12
Regression is no longer playable on level 1 plots (useless interaction).

Lines from the official Steam patch notes since Patch #18 that name this card.

Data: 9 Kings 1.0 card table on the official wiki, imported 2026-11-13.