[quote=@XxFellsingxX]
Working on the post. Just need to clarify one last thing: since they're up 10 feet above the ground, trying to jump down would cause them to take fall damage, right?
[/quote] That's right.

[quote=@XxFellsingxX]
If so, can Flicker jump down and attack (using Produce Flame) even if they take damage?
[/quote] You could still attack after jumping down. And since there's a cultist directly below the window and I'm using Tasha's rules for landing on creatures, Flicker could get in some extra damage by goomba stomping the cultist.

[quote=@XxFellsingxX]
(Sorry, still newish to 5e, not fully comfortable with combat rules ^^;)
[/quote] No worries. We've all been there at some point.