Cheapest priced copy (Commander 2017): $0.49 at Card Kingdom, near mint, their price list as of .
Territorial Hellkite 
Creature — Dragon · 6/5 · Rare · Tarkir: Dragonstorm Commander · #240
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.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
3 printings · $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2017 | 29 | Rare | $0.49 | — |
| Commander Legends: Battle for Baldur's Gate | 809 | Rare | $0.49 | — |
| Tarkir: Dragonstorm Commander | 240 | Rare | $0.49 | — |
5 rulings from Wizards of the Coast
- 25 August 2017If 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.
- 25 August 2017If 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.
- 25 August 2017Players may cast spells and activate abilities after a player is chosen at random for Territorial Hellkite but before it attacks that player.
- 25 August 2017If a player can't be attacked, that player can still be chosen at random.
- 25 August 2017Territorial Hellkite must attack the chosen player if able, not a planeswalker that player controls.