Is Kjeldoran Javelineer legal in Standard, Modern, and Commander?

Kjeldoran Javelineer is legal in: Modern, Legacy, Vintage, Commander, Pauper.

Kjeldoran Javelineer

Q: What type of card is Kjeldoran Javelineer?

Kjeldoran Javelineer is a Creature — Human Soldier. Its oracle text reads: "Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) {T}: This creature deals damage equal to the number of age counters on it to target attacking or blocking creature."

Creature — Human Soldier

Cumulative upkeep (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)