What's the timing for CH 3B:B?

You pretty much have to do it right when the first hit connects. It can be mashed out, but I don't think it's one of the easier ones to mash. I don't really remember tho.
 
I find it a better option than most of his 3B combos actually. It seems to come out on acccident when I intend to do CH 3B, 8A+K, B2 but hit B on accident just before I hit 8A+K. It hardly comes out when I intend it to. So, yeah. I mash it consistently but unintentionally.

Also, while we're on the subject, next to a ring, CH 3B B rings you out before it rings the opponent out, right? Does CH 3B 4B reduce the chances of self-ring outs?
 
I find it a better option than most of his 3B combos actually. It seems to come out on acccident when I intend to do CH 3B, 8A+K, B2 but hit B on accident just before I hit 8A+K. It hardly comes out when I intend it to. So, yeah. I mash it consistently but unintentionally.

Also, while we're on the subject, next to a ring, CH 3B B rings you out before it rings the opponent out, right? Does CH 3B 4B reduce the chances of self-ring outs?

Actually CH 3B,B rings out your opponent first and you'll usually teleport back onto the stage. CH 3B,4B can't self-ring out. Never seen it happen to me or another player, but its variable if it can hit your target sometimes. CH 3B,B is more reliable in my opinion. 3B:B is one of the few just frames I have yet to do consciously with Cervantes. Q_Q
 
It also comboes with 8B+K, and if they try to tech, it also techtraps( not sur if takes all). Another use for it is after iGDR while they are in the air, this will make a unblockable mid shot on wakeup.
 
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