Experiment Two

Evolve (Whenever a creature enters the battlefield under your control, if it has greater power or toughness than this, put a +1/+1 counter on this creature.)
Evolve (Whenever a creature enters the battlefield under your control, if it has greater power or toughness than this, put a +1/+1 counter on this creature.)
Whenever you would put a number of +1/+1 counters on Experiment Two, put one plus that