Polymorph
polymorph is an RPG platform—a tool kit and a set of development assets—that allows game designers to create easy-to-use and learn tabletop roleplaying games (TTRPGs). As a framework, it eliminates complex systems and esoteric rules mastery in favor of an elegantly simple yet satisfying core mechanic:
ROLL YOUR DIE TO SEE WHAT HAPPENS.
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No math
There is NEVER any math involved when you play polymorph. Depending on the game world and what kind of character you are playing, you may roll with advantage or disadvantage, and the game master never rolls dice.
You can learn more about polymorph here.