"Turbo Cannon's" effect name in the original is "Final Shot".
In episode 46, Rally Dawson uses this card during his Ground Duel against Yusei Fudo (It was originally Yusei Dueling against Roman Goodwin, but the latter made Rally take his place in the Duel near the end of the Duel). He Synchro Summons this card by tuning "Turbo Booster" (who Rally took control of via the effect of "Earthbound Immortal Uru") with "Turbo Rocket". Rally then activates this card's effect to destroy "Earthbound Immortal Uru" and inflict its ATK as damage to himself, winning Yusei the Duel.
In the anime, its effect could inflict damage equal to the total ATK of the monster it destroyed, rather than half of the ATK.