Harbor Serpent

+1: You gain 2 life. −1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn. −6: Create a white Avatar creature token. It has "This token's power and toughness are each equal to your life total."

At the beginning of your upkeep, you may gain 1 life.

Whenever you gain life, put a +1/+1 counter on this creature.

Flying Each opponent who cast a spell this turn can't attack with creatures. Each opponent who attacked with a creature this turn can't cast spells.

Enchant creature Enchanted creature gets +1/+1 for each Plains you control and has flying.

Flying

Flying, first strike, lifelink, protection from Demons and from Dragons

W, T: Tap target creature.