B3s and F3s can be used a few ways
- After a move with long hitstun, you can land a B3 or F3 to launch the opponent for a followup
- From a normal/string with decent cancel advantage you can cancel said normal/string into a bounce cancel, which is like a MB B3/F3 (ie it has armour on it) but you can cancel into it from a normal/string for the cost of
two bars
- From a juggle of some sort with enough height you can combo a B3/F3 from it
- F3s also have the property of hitting overhead so some characters can make theirs cross up in certain ways whether it be on oki or just off of a setup of some sort
As for combo breakers the closest thing to a breaker in this game is the wager mechanic, also knows as clash. You only have access to it once in the entire game, and you only get access to it on your second health bar. You initiate it like a breaker, with F+RT/R2 while you're being comboed, but it doesn't cost you any meter.
You'll see something along the lines of this on screen:
And these bars represent how many bars of meter both players have left. You can press 1, 2, 3, or 4 to spend 1, 2, 3, or 4 bars of your meter respectively, but you can only spend up to as many bars of meter as you currently have avilable. The player with the shield icon is the "Defender", the person who initiated the clash, and the person with the two swords icon above their bar is the "Attacker", the opponent.
If the Defender spends more meter than the Attacker, the Defender
regenerates health depending on the difference in bars of meter spent between the Defender and Attacker. For example if the Defender spends three bars of meter and the Attacker spends 1 bar of meter then the Defender wins the wager by two bars, and this gives the Defender 25% health back.
If the Attacker spends more meter than the Defender, the Defender
loses health depending on the difference in bars of meter spent between the Defender and Attacker. For example if the Attacker spends all four bars of meter and the Defender spends 1 bar of meter then the Attacker wins the wager by a difference of 3 bars, and the Defender takes 25% damage/loses 25% health.
Of course what happens all depends on the meter both players have, you could have any combination like some of the below:
So wager/clash can be a risk if you have less meter than the opponent because it means potentially taking damage instead of getting health back, but you might need to do it just to avoid a combo/setup that'll kill you, but if you have more meter then it's good because you get to regenerate health.
You also cannot be killed by a wager/clash, but you can be put at 1% if you lose enough health from it.
You can also play mindgames with your opponent and feint wagering meter by double tapping the meter burn button (R2/RT) during the wager sequence. This makes it look like you're spending meter even though you're not, and can be used for baiting the opponent into spending meter for example.
However, there is a new mechanic being introduced into Injustice 2 that works a little bit like a breaker called air teching. By pressing up up MB to air tech up the way or back back MB to air tech backwards while being juggled you can spend a bar of meter to perform a flip in the air either straight upwards or behind you and get out of the current combo. However you can be caught during the recovery of the air tech and be put back in the combo so this must be used carefully.
Hope this helps!
