Gladiator Proving Ground is a Normal Spell Card.
Spell Cards are usually activated from the hand on your turn unless their type gives another timing window.
On the current TCG and OCG Forbidden & Limited lists tracked here, Gladiator Proving Ground is Unlimited.
YGOPRODeck lists Gladiator Proving Ground for these formats: Common Charity, Edison, TCG, OCG, Master Duel.
Gladiator Proving Ground belongs to the Gladiator Beast archetype—use that tag when searching for engine pieces and tech options.
A listed print of Gladiator Proving Ground appears in Legendary Collection 2: The Duel Academy Years Mega Pack (LCGX-EN257) at Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Gladiator Proving Ground is about $0.57 on Cardmarket (prices change frequently).
