The oldest living being in the entirety of the Vale, more ancient than even the dragons, is Mysteriphal. The effective leader of the Harken Forest treants, he has sworn to protect the petrified husk of his patron Malorunth, until either his own death or Malorunth returns to life, whichever occurs first. Once, so long ago no creature can remember it, he was generous and kind, but centuries of war and death have scoured this goodwill from his being. Scars of ancient fires mark his form, and age has left rot in his joints and body, but he is one of the strongest individual beings in the Vale still and even other treants are cautious when dealing with him.

The program I use to make my 5e stat blocks is a little broken when it comes to Legendary Actions for unique creatures, and I haven’t figured out how to fix it for the picture. It’ll be written correctly in the plain text under the read more.

Originally from the 4e Monster Vault: Threats to the Nentir Vale.

5th Edition

Huge plant, true neutral
Armor Class 19 (natural armor)
Hit Points 162 (12d12 + 84)
Speed 20 ft.
Str 26 (+8) Dex 15 (+2) Con 24 (+7) Int 17 (+3) Wis 25 (+7) Cha 22 (+6)
Skills History +8, Nature +8, Perception +12
Damage Resistances bludgeoning, piercing
Senses passive Perception 22
Languages Common, Elvish, Sylvan
Challenge 13 (10000 XP)
False Appearance. While Mysteriphal remains motionless, he is indistinguishable from a normal tree.
Fire Catcher. Whenever Mysteriphal takes fire damage, he must succeed on a DC 15 Dexterity saving throw or catch on fire. While on fire, he takes 5 (1d10) damage at the start of each of his turns, and his Slam attacks deal an additional 5 (1d10) fire damage. Mysteriphal repeats the saving throw at the end of each of his turns, ending the effect on a success.
Legendary Resistance (3/Day). If Mysteriphal fails a saving throw, he can choose to succeed instead.
Siege Monster. Mysteriphal deals double damage to objects and structures.
Mysteriphal makes two Slam attacks.
Slam. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 18 (3d6+8) bludgeoning damage. If the target is a creature, it must succeed on a DC 15 Strength saving throw or be knocked prone.
Root Grab. Melee Weapon Attack: +13 to hit, reach 15 ft., one Large or smaller prone creature. Hit: The target is grappled (escape DC 16). Until this grapple ends, the target is restrained. Mysteriphal can grapple up to 4 targets at once.
Rock. Ranged Weapon Attack: +13 to hit, range 60/180 ft., all targets in a 20 foot line within range. Hit: 30 (4d10+8) bludgeoning damage.
Reverberating Word (1/Short Rest). Each non-plant creature within 15 feet of Mysteriphal must make a DC 15 Constitution saving throw against this magic. On a failed save, the target takes 45 (10d8) thunder damage and is deafened for one hour. If the saving throw fails by 5 or more, the target is also stunned for one minute. A stunned target can repeat the save at the end of each of its turns, ending the effect on itself on a success.
If the saving throw is successful, the target takes half as much thunder damage and is not deafened.
Charred For Life. When a creature deals fire damage to Mysteriphal, he can make a Slam attack targeting that creature.
Legendary Actions
Mysteriphal can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature’s turn. Mysteriphal regains spent legendary actions at the start of his turn.
Big Step. Mysteriphal moves up to his speed.
Root Grab. Mysteriphal makes one Root Grab attack.
Slam (Costs 2 Actions). Mysteriphal makes one Slam attack.

13th Age

Huge 11th level troop [plant]
Initiative: +12
Vulnerability: Fire
Sweeping Slam +16 vs. AC (4 attacks)C2A0- 50 damage
Dual Hit:C2A0If two sweeping slamC2A0attacks hit the same enemy, the target is also dazed until the end of MysteriphalE28099s next turn.
C: Root Grab +16 vs. PD (one nearby dazed or stunned enemy)C2A0- The target is grabbed. While grabbed, the target is weakened
Quick Use:C2A01/round, as a quick action.
C: Reverberating Word +16 vs. PD (1d3+1 nearby enemies)C2A0- 100 thunder damage and the target is dazed (save ends).
Natural 16+:C2A0The target is stunned instead of dazed (save ends).
Limited Use: 1/battle, but the ability recharges when Mysteriphal is staggered. If he hasnE28099t already used reverberating voiceC2A0when he becomes staggered, he uses it as a free action and then it recharges.
Ancient Entity:C2A0If Mysteriphal is confused or stunned, he is instead dazed for the same duration.
Firecatcher:C2A0When Mysteriphal takes fire damage, he also takes 10 ongoing fire damage. While taking any ongoing fire damage, MysteriphalE28099s sweeping slamC2A0attacks deal an extra 10 fire damage.
Teleport:C2A0As a move action when the escalation die is even, Mysteriphal can teleport to a nearby location that he can see.
Hardwood Resistance:C2A0Mysteriphal has resist damage 18+C2A0to all damage except fire and melee weapon damage.
ACC2A029 PDC2A027 MDC2A021 HPC2A0780
Nastier Specials:
Charred for Life:C2A01/round, as an interrupt action when an attack deals fire damage to Mysteriphal, he can use sweeping slam.

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