Is Life Matrix legal in Standard, Modern, and Commander?

Life Matrix is legal in: Legacy, Vintage, Commander.

Life Matrix

Q: What type of card is Life Matrix?

Life Matrix is an Artifact. Its oracle text reads: "{4}, {T}: Put a matrix counter on target creature and that creature gains "Remove a matrix counter from this creature: Regenerate this creature." Activate only during your upkeep."

Artifact

, : Put a matrix counter on target creature and that creature gains "Remove a matrix counter from this creature: Regenerate this creature." Activate only during your upkeep.