Is Nexos legal in Standard, Modern, and Commander?

Nexos is legal in: Legacy, Vintage, Commander.

What type of card is Nexos?

Nexos is a Creature — Human Tyranid Advisor. Its oracle text reads: "Strategic Coordinator — Basic lands you control have "{T}: Add {C}{C}. Spend this mana only on costs that contain {X}." *The blessed union of gun, claw, and merciless intent is a force to be truly feared.* Power/Toughness: 2/2"