Rhythm of the Wild
Enchantment
Some view Domri's unlikely ascent as a sign of Ilharg the Raze-Boar's imminent return.
Rulings (9)
If Rhythm of the Wild leaves the battlefield at the same time that a nontoken creature enters the battlefield (most likely because that creature has a replacement effect, such as that of Rescuer Sphinx), that creature still gets a +1/+1 counter or haste.
If a creature enters the battlefield with two instances of riot, you may choose to have it get two +1/+1 counters, one +1/+1 counter and haste, or two instances of haste. Multiple instances of haste on the same creature are redundant, but we're not going to tell the Gruul how to live their lives.
If you choose for the creature to gain haste, it gains haste indefinitely. It won't lose it as the turn ends or as another player gains control of it.
Legality
Formats by platform