Fury is a level from 0 to 7. It does not go up just because the round number did.

Rage dice are the pile you spend. Start of every battle round: gain Rage equal to your current Fury. End of the round, leftovers are gone. Next round you draw again. You do not keep a stash.

Once, in deployment: attacker Fury 1, defender Fury 2. That's the roll-off (attacker/defender), not who takes the first turn.

If nobody changes Fury: attacker stays at 1 and gets 1 Rage each round. Defender stays at 2 and gets 2. Round 2 is not "now you are 2 and they are 3."

Fury only moves when an ability below says so. A 6 on Eruption of Fury raises the opponent's Fury. Fight Through the Pain drops yours when you spend Rage. Ignite Fury at a Place of Power is +2 Fury and +2 Rage.