Hermaeus Mora, Gardener of Men

As an additional cost, pay {b/g}{b/g} and pay 5 life.
When Hermaeus Mora, Gardener of Men enters
the battlefield, choose one.
•Gain control of target creature with mana cost
6 or less.
•You may cast spells without their mana cost
until end of turn. Lose 6 life for each spell played
this way.
Whenever a player would get a counter, double
the amount of counters gained.