Sorry for stealing from Terakhan

Whenever a creature enters, you may add an amount of equal to the number of creatures you control that share a creature type with it.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead. If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Whenever another creature you control enters, put a +1/+1 counter on that creature and a +1/+1 counter on this creature.

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy. Equip

Marath enters with a number of +1/+1 counters on it equal to the amount of mana spent to cast it. , Remove X +1/+1 counters from Marath: Choose one — • Put X +1/+1 counters on target creature. X can't be 0. • Marath deals X damage to any target. X can't be 0. • Create an X/X green Elemental creature token. X can't be 0.

If one or more tokens would be created, twice that many of those tokens are created instead. If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.