The Ace Blade (エースブレード Ēsu Burēdo) is a weapon made of energy used by Ultraman Ace. Ace summons the blade through use of his Ultra Psychokinesis, and generates it from his own energy. Ace typically uses this weapon in extreme cases, as shown when he killed Doragory using it, and through sheer determination, as seen when he killed Sphinx after the death of the Orion girl Michiru. The Ace Blade takes the form of a Katana without a hilt, and Ace typically performs several dramatic techniques with it before using it, such as twirling it around in his hands.
Ace Blade's first appearance, being summoned by Ace as a last-ditch attack against Doragory
The Ace Blade is one of the few Ultra Weapons to not come from a bracer of any kind, instead it comes from Ace's own power.
The Ace blade hasn't made many TV appearances since the Showa era, but is commonly used by Ace in stage shows.
In the Showa era series, the Ace Blade is a Katana (刀,Katana) but in Ultraman Land stage shows, it took the form of a Bokutō (木刀,Bokutō), a class of sword commonly used for training. The reason for this change is to avoid unlikely accidents or injuring the actors by mistake.
Due to this, the Ace Blade is now one of the Showa Era weapons that is now rarely used in newer installments of the franchise. Other examples include the Ultra Magic Ray, Taro Bracelet and Leo Nunchaku.