If a player tries to open the arena exit without fighting Dad, he will shout "No human pass through arena without defeating Dad!" and attack the player. He will also ignore the player if talked to. Once Dad is defeated, the player can no longer attack him. Trying to attack him yields the message "You don't need to fight him again."
Dad is larger and stronger than normal trolls, and he can easily hit into the 20s. While his hits are normally slow, his coding can sometimes cause a rapid second hit; players should prepare to take up to 54 damage within a few hits, if not using prayer. He also has a 1/3 chance of doing a giant swing that sends players flying through the air, knocking them back and momentarily stunning them; this attack can be somewhat negated by standing near a wall, ignoring the knockback effect, but retaining the stun. Protect from Melee is recommended when fighting him, and will block all damage.
Safespot
Dad is non-aggressive, allowing players to set up a safespot. Since his dialogue can be skipped prior to fighting, players can stand next to the entrance gate to the arena and attack Dad from a distance. Alternatively, since Dad is unable to walk through players, it's possible to have a friend or other player stand in his way, so he can't get close enough to attack.
Dad will stop the player from attacking just before he dies, asking for his life to be spared. This option is recommended, as killing him after he has surrendered will cause the troll spectators in the arena to become aggressive. If spared, he allows players to pass through the northern gate, although the mountain trolls further down the path will still be aggressive.
In the February 2022 Postbag From the Hedge, it is revealed that Dad's defeat at the player's hands caused him to reflect on the "toxic masculinity" present in troll culture that encourages fights. He subsequently ends the tradition of the "Dad" family name and names his son Mam.
The sound effect that plays when Dad becomes aggressive after agreeing to fight him through dialogue is the same sound that plays when either Tumeken's Warden or Elidinis' Warden is restored at the end of phase 2 of the final battle in Tombs of Amascut.