The little numbers that are circled (by the characters' names) are the Levels.

If it says 7(11) that means that the character needs to roll a '7' or less to hit (past all defenses).  To merely hit the other character (and hit "on" their defense) would be the second number (11 or less, in this case) and anything higher would be a miss.

So for a 7(11) that means that the player rolls a d20.

1-7 Hit
8-11 Hits on the active defense (it might pass right through them, or hit on the defense and be ignored by the character)
12-20 Miss (and thus a chance for the attack to go wild and strike something or someone else)