Hold Breath. The lizardfolk can hold its breath for 15 minutes.

Multiattack. The lizardfolk makes two melee attacks, one with it's bite and one with it's claws.

Bite. Melee Weapon Attack:  +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) piercing damage, or 7 (1d10 + 2) piercing damage in crocodile form. If the lizardfolk is in crocodile form and the target is a Large or smaller creature, the target is grappled (escape DC 12). Until this grapple ends, the target is restrained, and the lizardfolk can't bite another target. If the lizardfolk reverts to its true form, the grapple ends.

Claws (Lizardfolk Form Only). Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) slashing damage.

Change Shape. The lizardfolk magically polymorphs into a crocodile, remaining in that form for up to 1 hour. It can revert to its true form as a bonus action. Its statistics, other than its size, are the same in each form. Any equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies.

Bonus Action: Bolster Allies. One creature of the Shaman's choice that it can see within 30 feet of it gains 1d8+3 temporary hit points.

Escape Manoeuvre. As a reaction when it takes damage, the Shaman may use its Change Shape and move up to it's speed.

Villian Actions:

Round 1:  The Shaman calls up thick plant growth and muck, making the area difficult terrain for all creatures of it's choice. Each creature of it's choice can move up to half their speed.

Round 2: Each creature of the Lizardfolks choice can make a grapple against a creature within 5 feet of them, and then move up to half their speed.

Round 3: Each creature of the Lizardfolks choice that has a creature grappled can move up to half their speed, attempt to knock the grappled creature prone, then make a melee attack.