Yugi Tatsuki

Yugi Tatsuki, designated as Subject 10 (被験者10), is the main antagonist of Interstellar.

He was the emperor of the AXEL Realm before being captured and turned into a soldier by the Evolutionary. Yugi, however, went rogue and disappeared for many years until finally re-appearing at the Interstellar Tournament. Seeking to merge the "base world" with AXEL Realm, Yugi intercepted the tournament with the intention of killing its competitors.

This put him into conflict with Silver and his team, who eventually defeated him in a duel, but not before Yugi destroyed the tournament grounds.