An Ante Duel is a Duel where both players stake cards of equal value, and the winner of the Duel claims both cards. This is the only way to become the owner of a card in a Duel. These Duels are completely optional but are forbidden in most official tournaments.
Anime and manga
In the anime and manga, these Duels were more common. In the manga, ante is said to be a common rule in trading card games, and Ante Duels were required in the Battle City tournament.
In Yu-Gi-Oh! GX, however Duel Academy's policy forbids Ante Duels between students. In season one of GX, there were a few cases of Ante Duels. Despite posing as a Shadow Duelist, Titan would also take all rare cards away from his opponents. Brier and Beauregard, challenged Obelisk Blue students in unauthorized Ante Duels before Dr. Crowler "hires" Jaden to defeat them. Later is introduced Trapper, a man who takes most valuable cards from his opponents, and later sells them for a great amount of money.
In Yu-Gi-Oh! 5D's, Yusei Fudo chose to win back his "Stardust Dragon" from Jack Atlas via a one-way Ante Duel, even after Jack offered to just give it back. In the English dub, the final Duel of the Fortune Cup was rewritten as this - Jack would take back "Stardust" if Yusei lost.
In Yu-Gi-Oh! ZEXAL, Number holders win the "Numbers" used by their opponents if they win. At the beginning of the series, Yuma Tsukumo challenges Reginald Kastle to an Ante Duel for Bronk Stone's Deck, wagering his own. Later on, Kite and Jinlon have a Duel in which they wager "Galaxy-Eyes Photon Dragon" and "Number 46: Dragluon", respectively. If a Barian was killed, they leave nothing behind, except for their soul. The Barian's soul contains the "Numbers", which can be claimed if someone absorbs that Barian's soul, as seen when Vector absorb the souls of Marin and Dumon, respectively, after defeating Marin in a Duel.