I was confused for a bit how revenge/attacking works but this is how it goes (at least as I noticed by now, game changes all the time):

Wild/heroic
- You can't attack players less than 10 lvls.
- You can continue attacking another player unless you win, so the other player is transported to aerie.
- The player you attacked can now revenge you back.

Caribbean
- You can attack anyone.
- You can keep attacking every 5 mins
- The player you attacked can now revenge you back.

Revenge log
- When you attack someone from your revenge list and you win fight, he/she can revenge you back. You can't revenge until the other player revenges back and wins the fight.
- When you attack someone from your revenge list and you loose, he/she can't revenge you back. You can revenge again next day and that player can't revenge you back until you win the fight.

Another thing related to this I recently noticed that the rewards taken from the player loosing the fight are not transferred to the player winning (winner takes only a part of the rewards) so i wonder where the rest goes?