Corrupted Forest God

Legendary Rider. While mounted on the Spectral Panther, he has advantage on saves against being knocked prone and can cast spells without somatic components.

Rebirth of Wildfire (1/day). When reduced to 0 HP for the first time, the Forest God instead melds with his panther mount to become the Aspect of the Wild Curse.

Multiattack. The Forest God makes two attacks in any combination.

Staff of Rootrot. Melee Weapon Attack: +9 to hit, reach 5 ft., one target.
Hit: 13 (2d8 + 4) bludgeoning + 9 (2d8) necrotic. The target must succeed on a DC 17 Strength save or be restrained by grasping roots for 1 minute (repeat save at end of each turn).

Call of the Verdant Curse (Recharge 5–6). All creatures within 30 ft. must make a DC 18 Constitution save or be cursed for 1 minute. While cursed, they take -2 to AC and have disadvantage on saving throws against plants and beasts.

Corrupted Nature Magic.The Forest God can cast druid spells using Wisdom as his spellcasting modifier (spell save DC 18, +10 to hit). He doesn't need material components.

At-will: druidcraft, thorn whip, entangle
3/day each: blight, conjure animals, wall of thorns
1/day: insect plague, geas, awaken

Legendary Actions (3/round)

Vine Lash (1 action): Target within 30 ft. must make a DC 16 Dex save or take 11 (2d10) slashing and be pulled 10 ft.

Withering Gaze (1 action): Target within 60 ft. takes 10 (3d6) necrotic damage and must pass a DC 16 Con save or lose 10 ft. of movement until the end of its next turn.

Summon Corrupted Sapling (2 actions): A vine-covered fey spirit emerges (use dryad stats with poison-themed spells), acting on initiative count 20 (loses this action if used more than once).