Wikia

For the monster known as "Shooting Quasar Dragon" and the Limit Over Accel Synchro see here.

Delta Accel Synchro Summon (デルタ・アクセル・シンクロ) is a form of Synchro Summoning in the anime, in which there is one Tuner Synchro Monster and two non-Tuner Synchro Monsters used in the Synchro Summon. The only known Delta Accel Synchro Monsters are "T.G. Halberd Cannon" and "Cosmic Blazar Dragon". "T.G. Halberd Cannon" was used by Antinomy, when performing Top Clear Mind in episode 144. It has also been shown that performing Delta Accel successfully can cause a nearby star to explode with a black hole forming in its place. According to Antinomy, this is a Synchro surpassing Accel Synchro.^[1]