These use a basic spell projectile, a large nuke with high base damage and a triple shot.
The last 2 have quite long cooldowns. The triple shot casts their basic projectiles 3 times in quick succesion.
The longer CD skills seem to benefit pretty heavily from Spell Echo support.
These are actually quite cool with return on their normal projectiles and the triple shot; should make them pretty good for clear.
Their nukes break with return sadly.
These can be found in the tunnels contract in heist.
"I am Iron man"
These were suggested by @zachhee, thank you!
I appreciate all the suggestions coming in, feel free to message me or leave a comment if you would like a video made of a spectre you like.
This video was recorded in patch 3.22.