Bulbasaur

Overgrow.
When Bulbasaur is below half its hit points, it deals an extra 2 damage with any attack that deals poison or plant-based damage.

Photosynthesis.
If Bulbasaur starts its turn in sunlight, it regains 2 hit points.

Amphibious.
Bulbasaur can breathe both air and water.

Tackle. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 1d6 + 2 bludgeoning damage.

Vine Whip. Melee Weapon Attack: +4 to hit, reach 10 ft., one target. Hit: 1d8 + 2 slashing damage. The target must succeed on a DC 11 Strength saving throw or be pulled 5 feet closer to Bulbasaur.

Leech Seed (Recharge 5–6).
Bulbasaur fires a seed at one creature within 30 feet. The target must succeed on a DC 11 Constitution saving throw or become seeded. At the start of each of the target’s turns for 1 minute, it takes 1d4 necrotic damage, and Bulbasaur regains that many hit points. The target can repeat the saving throw at the end of each of its turns to end the effect early.

Grow.
Bulbasaur flexes its leaves and empowers itself for the next round. Until the start of its next turn, it gains a +2 bonus to damage rolls and has advantage on one Strength check of its choice.

Protective Vines.
When Bulbasaur's trainer or ally within 5 feet is hit by an attack, Bulbasaur can use its reaction to lash out with vines and try to deflect the blow. The target gains a +2 bonus to AC against that attack, provided Bulbasaur is not incapacitated.