Urichinan
@Urichinan
Bursts also can only be done when you have a Burst icon. In BBCSE you start the first round with 1 Burst and if you lose the first round you gain a second one. Once you've used both Bursts you can't do them anymore.Bursts are essentially a combo breaker that isn't 100% safe.
In P4U and GG Bursts will recover themselves over time, and you can use them again, though they have other uses aside from being combo breakers.
Bursts in BB, P4U and GG are nothing like Pushblocking at all. Though BB and GG do have Barrier Guard and Faultless Defense which will slowly push the character back the more they do moves, though it's not a single push like with Pushblock, but rather increasing the pushback on each move's hitstun.
Injustice seems to be going for a mix of both GG and Marvel's systems, with it taking meter to use like in GG, but being a single push like in Marvel.