Door of Shadows on my Warlock will seriously become my most missed ability from Shadowlands.
It is the singular reason why I’ve only played Venthyr on my Warlock, together with lore reasons.
Door of Shadows, with Theotar/Leisurely Gait soulbind, has become my default movement ability in raid fights and dungeons. It has always at least one charge on cooldown!
It is just perfect for positioning the “warlock turret” in between casts, skipping damaging areas on the ground or letting the target run away while I finish my last cast before I can teleport right up to them again.
Need to do that raid boss mechanic? Door of Shadows away, Demonic Circle back again.
Your slow Warlock is falling behind? Door of Shadows a shortcut.
It is even useful in PvP with Nadjia/Agent of Chaos soulbind as an initating ability.
I was very sad to not see it on the Warlock talent tree for Dragonflight. To me, it is a gameplay defining ability. I am not happy to be forced to walk slowly everywhere again.