Is Simic Ascendancy legal in Standard, Modern, and Commander?

Simic Ascendancy is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Simic Ascendancy

Q: What type of card is Simic Ascendancy?

Simic Ascendancy is an Enchantment. Its oracle text reads: "{1}{G}{U}: Put a +1/+1 counter on target creature you control. Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on this enchantment. At the beginning of your upkeep, if this enchantment has twenty or more growth counters on it, you win the game."