Blue centipede

Magical weapons 

The blue centipedes attacks are magical.

Blue shell

The blue centipede is immune to any ranged attack that uses arrows.

Multi attack

The blue centipede makes two attacks one with its bite and two with a it’s claw.

large Bite

Melee Weapon Attack: +7 to hit, reach 20 ft., 1 target. Hit: 17 (3d10 + 7) piercing damage. 

Large claw

melee weapon attack: +7 to hit, reach 20 ft., 1 target. Hit: 17 (3d10 +7) slashing damage.

Squish

melee weapon attack: +7 to hit, reach 10 ft., 2 target. Hit 17 (3d10 +7). Bludgeoning damage. Target must make a dc 18 dexterity check or be knocked prone for 30 seconds.

Blue spit

RangedWeapon Attack: +7 to hit, range 5/300 ft., 1 target. Hit: 17 (3d10 + 7) acid damage. The target must make a dc 15 constitution check or take a extra 2d8 fire damage.

Burrow recharge 6

The blue centipede burrows and creates a huge stone shell (Ac 15 hp 15 immunity to poison and physic damage)and the blue centipede is fully protected in till it breaks and the blue centipede can use the blue spit action while inside.

Large claw

The blue centipede make one large claw attack.

Terraformed claw (Costs 3 Actions). 

The blue centipedes claw becomes terraformed meaning that for 18 seconds when the blue centipede uses the large claw it does and extra 2d8 acid damage when it hits.

Huge roar  (Costs 3 Actions)

The blue centipede lets out a roar and any one that can hear it must make a dc 17 dexterity check on a Success it does nothing but on a fail the target is deafened for 1 minute.