Telepathic Control. The fortress is controlled telepathically and has no manual controls.

Telepathic Broadcast. The fortress can emit telepathic messages to all devils within a 1-mile radius.

Telepathic Disruption. The fortress can disrupt all telepathic communication within a 1-mile radius.

Fortress Teleportation. As an action, the fortress can prepear to teleport up to 1 mile to an unoccupied space on its next turn.

 Hellfire Beam (3/Day). The fortress fires a continuous beam of hellfire in a 5-foot wide, 300-foot long line. Each creature in the line must make a DC 18 Dexterity saving throw, taking 33 (6d10) fire damage and 33 (6d10) radiant damage on a failed save, or half as much on a successful one. The beam lasts for up to 5 rounds (30 seconds), requiring concentration, and creatures must repeat the saving throw at the start of each of their turns while in the beam.

Devil Deployment (Recharge 1-3). The fortress deploys 3d6 devils, which descend to the battlefield and become active 2 rounds later. The DM chooses the types of devils deployed.

Harpoon Strike (Recharge 4-6). Ranged Weapon Attack: +18 to hit, range 300 ft., one target. Hit: 97 (15d12) piercing damage. This attack targets the heaviest armored creature within range.

120mm HE Fireball Barrage (Recharge 5-6). The fortress bombards a point within 300 feet. Each creature in a 40-foot radius sphere centered on that point must make a DC 18 Dexterity saving throw, taking 66 (12d10) fire damage on a failed save, or half as much damage on a successful one.

380mm HE Fireball Barrage (Recharge 6). The fortress unleashes a devastating barrage on a point within 300 feet. Each creature in an 80-foot radius sphere centered on that point must make a DC 20 Dexterity saving throw, taking 209 (38d10) fire damage on a failed save, or half as much damage on a successful one.

Zariel's Flying Fortress can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. Zariel's Flying Fortress regains spent legendary actions at the start of its turn.

Harpoon Strike. The fortress uses its Harpoon Strike if available.

Hellfire Beam. The fortress uses its Hellfire Beam if available.

Deploy Devils (Costs 2 Actions). The fortress uses its Devil Deployment ability if available.

Teleport (Costs 2 Actions). The fortress uses its Fortress Teleportation ability.

Full Barrage (Costs 3 Actions). The fortress uses both its 120mm and 380mm HE Fireball Barrages if both are available.