Little update here: As I’m finally playing unmodded again (for achievements / Honour Mode), I can confirm this bug exists in the unmodded game.
I’m also pretty good at replicating it now:

Whenever Halsin concentrates on a spell, he can’t cast Healing Word. Right now, I tried with Moonbeam:

- casting Healing Word first, then Moonbeam —> works
- casting Moonbeam first —> Healing Word is greyed out on all levels
- cancelling Moonbeam —> Healing Word remains greyed out briefly, but changing back and forth between tabs on the hotbar makes it available again

This issue only occurs during combat. Outside of combat, Healing Word can be cast while concentrating on a different spell.

Last edited by Strato Incendus; Yesterday at 11:00 PM.