I have a creature with the Lyra trait which as part of the trait sends them to the bottom of the timeline when they take damage. I’ve noticed in the combat log that they seem to get sent to the bottom of the timeline even if no damage is taken (in this case I think the map has reflect damage but Spiritual Attunement prevented it) :
***** Your Abyssal Wisp attacks! *****
Abyssal Wisp was sent to bottom of the . (Lyra)
Abyssal Wisp Prevented! ( Spiritual Attunement)
Abyssal Wisp took 0 damage. (Realm)
Koloss Eradicator took 2587 damage.
Koloss Eradicator was killed.