Effortless

Effortless is a Class 1 Difficulty, and the easiest official difficulty. However, it got removed from JToH. Fun fact: this was the only difficulty to be removed that was not soul crushing or harder.

Towers this is in

 * Tower of Slight Unhappiness (ToSU)
 * Tower of Teaching (ToT)
 * Tower of Pure Calmness (ToPC)
 * Tower of Almost No Despair (ToAND)

Towers this is with

 * Great Citadel of Difficulty Chart (GCoDC)
 * Great Citadel of Hellish Difficulties (GCoHD)
 * Great Citadel of Custom, Impossible and Normal Difficulties (GCoCIaND)
 * Monolith of Completely Endless Difficulties (MoCED)