What if the act of attacking/defending a travel portal created bandits, just like trying to steal gold from mines?
After a certain amount of HP is lost or healed, bandits would spawn to attack the players.
To avoid making too hard to defend or attack both Attackers and defenders would have a unique buff: a huge damage bonus against the Thieves, so they can kill with ease But Will die If stay AFK
They gonna be kinda easy to kill and drop some Gold aswell
Their spawn rate can be one of 1 maybe 2 minutes or maybe more like 5 or 10
Or can be based on the state of How much has already been drained or healed