Demon Tower (5e Creature)
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Huge swarm of Small fiends (heartless), chaotic evil
Saving Throws Str +11, Dex +13, Cha +13
Consume. Any creature that is grappled by the demon tower is restrained and is trapped inside the demon tower. Grappling a creature does not halve the demon tower's speed. A creature grappled by the demon tower takes 3 (1d6) necrotic damage at the start of each of its turns.
Legendary Resistance (3/Day). If the demon tower fails a saving throw, it can choose to succeed instead.
Siege Monster. The demon tower deals double damage to objects and structures.
Multiattack. The demon tower can use its Frightful Presence. It then makes three attacks: two with its dive and one with either its hook or uppercut.
Dive. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 16 (2d8 + 7) necrotic damage.
Hook. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 18 (2d10 + 7) necrotic damage. On a hit, the target creature must make a DC 21 Strength saving throw or be pushed 15 feet in a direction the demon tower chooses.
Frightful Presence. Each creature of the demon tower's choice that is within 120 feet of the demon tower and aware of it must succeed on a DC 21 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the demon tower's Frightful Presence for the next 24 hours.
Rise (Recharge 5-6). The demon tower spreads itself to cover all creatures within 60 feet of itself, allowing the countless shadows that make it up to swarm everything around it. Each creature within 60 feet of the demon tower must make a DC 21 Dexterity saving throw. On a failed save, a creature takes 49 (14d6) necrotic damage and is knocked prone. On a successful save, a creature takes half as much damage and isn't knocked prone.
Aggressive. The demon tower moves up to its speed toward a hostile creature that it can see.
The demon tower 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. The demon tower regains spent legendary actions at the start of its turn.
Attack. The demon tower makes one dive attack.