Territorial Hellkite

Flying, haste
At the beginning of combat on your turn, choose an opponent at random that this creature didn't attack during your last combat. This creature attacks that player this combat if able. If you can't choose an opponent this way, tap this creature.

Tarkir: Dragonstorm Commander

Commander Legends: Battle for Baldur's Gate

Flying, haste
At the beginning of combat on your turn, choose an opponent at random that Territorial Hellkite didn't attack during your last combat. Territorial Hellkite attacks that player this combat if able. If you can't choose an opponent this way, tap Territorial Hellkite.

Commander 2017

Treasure Chest

If Territorial Hellkite can't attack the chosen player, it's free to attack any other player or planeswalker or to not attack. If there's a cost associated with attacking the chosen player, it's free to attack any other player or planeswalker or to not attack. But if there's a cost associated with Territorial Hellkite attacking at all, Territorial Hellkite has to attack the chosen player or not attack.

If Territorial Hellkite didn't attack during your last combat, most likely because it was tapped or you didn't control it at that time, then any opponent can be chosen at random.

If a player can't be attacked, that player can still be chosen at random.

Players may cast spells and activate abilities after a player is chosen at random for Territorial Hellkite but before it attacks that player.

Territorial Hellkite must attack the chosen player if able, not a planeswalker that player controls.