Artists included:

-AnonTheAnon - https://twitter.com/RealAnonTheAnon
-BeepBeepPone - https://twitter.com/NoodlyLoodly
-BUCKyouALL - https://twitter.com/iWILLbuckYOU
-Chrysalisdraws - https://twitter.com/chrysalisdraws
-Crade - https://baraag.net/@Crade
-DimFann - https://twitter.com/DimFann
-Expression2 - https://twitter.com/e2ponies 
-Forsaken - https://twitter.com/Forsaken3d
-Four Eyes - https://twitter.com/FourEyes_T
-Jargon Scott - https://twitter.com/Jargon_Scott
-Lyrabop - https://twitter.com/lyrabop
-LockHeart - https://twitter.com/Lockuheart
-Mkogwheel - https://twitter.com/MkogwheelR18
-Opossum-Imoto - https://twitter.com/opossum_imoto
-Pabbles - https://twitter.com/pabbley
-Parumpi - https://twitter.com/parumpi
-Pony Quarantine - https://twitter.com/PonyQuarantine
-Ratio - https://derpibooru.org/tags/artist-colon-ratiodaze
-Rhorse - https://twitter.com/Roghorse
-Some Leech - https://www.fimfiction.net/user/291894/Some+Leech
-Task - https://twitter.com/MinusculeTask
-TJPones - https://tjpones.com/
-wenni - https://www.pillowfort.social/wenni
-wren - https://ponerpics.org/profiles/wren
-ZippySqrl - https://twitter.com/ZippySqrl

To the anon who made the piece (derpibooru.org/1139079, twibooru.org/882459) that inspired wenni's Twilight/Evil Celestia image: it's pretty rad, thanks.

All characters depicted are over 18, that's as big as they'll get.