dave2008
Legend
Looks good; however, you've blown the attack CR budget by making bucket chain blade a one action Legendary Action. Technically the DPR on this thing is 704. If you make it 2 or 3 actions then your down to 352 DPR, still to high for the CR, but closer. If your set on a CR of 20, you will have to loose the legendary action entirely or reduce the damage it causes. Personally, I would loose the legendary actions. Make "Tank the Hit" a reaction and Trembling Strike a recharge action. Something like this maybe (not sure on the frequency of Tank the Hit):
ACTIONS
Mulitattack. Old scoopy makes a Bucket Chain Blade and a Crude Blast attack, if it is available.
Bucket Chain Blade. Old scoopy picks an area within 80 feet of it an dig its bucket chain in a 40-foot line that is 15 feet wide. Each creature in that line must make a DC 23 Dexterity saving throw, taking 88 (16d10) slashing damage on a failed save, or half as much damage on a successful one.
Crude Blast (Recharge 5-6). Old Scoopy exhales a virulent crude Oil in a 120-foot line that is 10 feet wide. Each creature in that line must make a DC 22 Dexterity saving throw, taking 45(10d8) necrotic damage on a failed save, or half as much damage on a successful one.
BONUS ACTIONS
Trembling Strike (Recharge 5-6). Old Scoopy strikes the ground with its bucket chain blade, triggering an earth tremor. All other creatures on the ground within 60 feet of Old Scoopy must succeed on a DC 25 Strength saving throw or be knocked prone.
REACTIONS
Tank the Hit (Recharge 5-6). On a successful hit, Old Scoopy takes no damage.
ACTIONS
Mulitattack. Old scoopy makes a Bucket Chain Blade and a Crude Blast attack, if it is available.
Bucket Chain Blade. Old scoopy picks an area within 80 feet of it an dig its bucket chain in a 40-foot line that is 15 feet wide. Each creature in that line must make a DC 23 Dexterity saving throw, taking 88 (16d10) slashing damage on a failed save, or half as much damage on a successful one.
Crude Blast (Recharge 5-6). Old Scoopy exhales a virulent crude Oil in a 120-foot line that is 10 feet wide. Each creature in that line must make a DC 22 Dexterity saving throw, taking 45(10d8) necrotic damage on a failed save, or half as much damage on a successful one.
BONUS ACTIONS
Trembling Strike (Recharge 5-6). Old Scoopy strikes the ground with its bucket chain blade, triggering an earth tremor. All other creatures on the ground within 60 feet of Old Scoopy must succeed on a DC 25 Strength saving throw or be knocked prone.
REACTIONS
Tank the Hit (Recharge 5-6). On a successful hit, Old Scoopy takes no damage.