User blog comment:ZSomji16/The Flash (Season 4), Arrow (Season 6), Legends (Season 3), and Supergirl (Season 3) Villains and Big bads/@comment-24152851-20170327122115/@comment-27700324-20170328041333

Yeah, i guess that could work. I haven't read Arrow vengeance yet, but i think he has a similar mask to Brother Blood as the character was described in it. So it would be cool if he had a red one with a design slightly similar to the one of the Trigon of the comics. He could also make the cult come back with characters like Cyrus Gold finally become Solomon Grundy.

Well Slade did still fight him so to me it counts. I'm not sure if Oliver fought Trigon in any story though... I'll have to check.