>>92537819Because his relationship with the Flash is full of petty, personal shit that makes any time he shows up a giant red flag that shit has immediately gotten real.
Batman can fight the Joker a bajillion times and it always ends the same way, and whenever the Joker has Bats at his mercy all that happens is some convoluted deathtrap he escapes as soon as he wakes up because the Joker doesn't REALLY want Bats dead.
Reverse Flash will fuck the Flash RIGHT THE FUCK UP, and when he can't touch Flash, he does awful shit to everyone around him. He's terrifying in a fight, and whats worse than that is with Speedforce bullshit powers if you don't know where he is he is 1000x more dangerous, because if you can't see him he is probably placing a tiny amount of cyanide in every bowl of cereal you have ever eaten so he can poison you over time and land the killing blow with a feather in the present.