Tunnel Hunter. Dasos Silva borrow around until they sense prey, which then they launch out and try to swallow it whole if they can't they will sting it with their tail killing it instantly then eating it.

Symbiotic habitat. Dasos Silva provides a habitat to several creatures which it can call upon to protect it  (symbiotic shambling mound)

Multiattack

Swallow. If Dasos Silva makes a bite attack if if the target is medium-tiny creature they swallow it whole.

Bite. Melee Weapon Attack: +9 to hit, reach 15 ft., 4 target. Hit: 4d12 + 9 crushing damage and 1d10 piercing damage.

Sting. Melee Weapon Attack: +9 to hit, reach 10 ft., 1 target. Hit: 4d12 + 9 piercing damage the next 1d6 turns the target takes 1d12 poison damage at the start of every turn.

All actions it can do it can do as a bonus action but can't use multiattack.

Call To Arms. Summon 1d4 symbiotic shambling mound.

Dasos Silva can use legendary actions as normal actions but instead when it is not its turn or it could not use actions for 2 turns and use this unique legendary action.

Vine whip (Costs 2 Actions). Dasos Silva summons 1d4 medium vines which attacks the nearest creatures dealing 2d10 piercing and bludgeoning.

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Mythic Action Name (Costs # Actions). Enter the description for your mythic action.