Yuichi Hirose's (Alive: The Final Evolution) Void can annihilate any and all matter it strikes, hollowing out an entire mountain when empowered by Akuro's heart.
Killy (Blame!) using his Gravitational Beam Emitter to fire deadly beams of gravity that cannot be blocked, and can destroy the space-time continuum of the target location.
Noel Vermillion's (BlazBlue) Arcus Diabolus: Bolverk causes a dimensional collapse of a point in line with the barrels, bypassing walls and defense.
Hakumen (BlazBlue) wielding the Interfectum Malus: Ōkami, which allows him to cut through anything: timelines, dimensions, and the abilities of Ars Magus.
Baraggan Louisenbairn's (Bleach) Respira rots and destroys absolutely everything: flesh, buildings, barriers, and even the inside of himself.
Shūkurō Tsukishima's (Bleach) Book of the End is a sword of high attack power that can literally cut through anything, including the timeline of the target's memory and existence.
Genryūsai Shigekuni Yamamoto's (Bleach) Zanka no Tachi, Higashi: Kyokujitsujin will incinerate everything that touches its edge into nothingness.
Kenpachi Zaraki's (Bleach) Nozarashi can slice through anything, even a meteorite or the dimensional prison of an outer space vacuum that he was imprisoned in.
Lille Barro's (Bleach) The X-Axis does not use bullets, but simply pierces everything between the muzzle of his rifle and the target, with no barriers in between capable of blocking it.
The Sword (Cardcaptor Sakura) can cut through anything, including magical barriers, The Shield, and the space-time continuum.
The One Being Sought's (Code:Breaker) Sever removes slivers of space from his targets, making it impossible to block the massively aggravating cuts.
Vergil (Devil May Cry) wielding the Yamato sword that can cut through space and dimensional barriers, completely destroying defenses put up by the opposition.
Janemba (Dragon Ball Z) channeling his reality warping power through his Dimension Sword, allowing him to cut through anything.
Kuro'udō Akabane's (Get Backer) Bloody Sword can slash through space-time, and Akabane cannot imagine anything it cannot cut.
InuYasha (InuYasha) using the Meidō Zangetsuha to fire blades that slice through anything and drag them into the netherworld, and even allows the user to escape from the netherworld via the same method.
Tsubame Fury's (Kagijin) Splitting Void can cut through anything in existence, distance is no matter either.
Kakashi Hatake (Naruto) using Kamui Shuriken, which warps anything they cut into the other dimension, making it unblockable the moment it strikes the target.
Obito Uchiha (Naruto) using his Truth-Seeking Ball, which have the ability to destroy any and all matter, and nullify all techniques, even neutralizing an immortal revived corpse's regenerative abilities.
The Spear of Longinus (Neon Genesis Evangelion) can pierce all A.T. Fields, and thus nothing can block it.
Palkia (Pokémon Adventures) using Spacial Rend to slash open space, leaving a dimension line behind that makes it impossible to block, sending the target to another location at the same time.
Akua Shuzen (Rosario + Vampire: Season II) using the Dimension Blade, a dark art technique that cannot be blocked because it shifts the attack to another dimension and back.
Excalibur Sonic (Sonic the Hedgehog) wielding the Excalibur, which has an unblockable edge due to the tremendous magic and cut through even the Dark Queen.
Kojō Akatsuki's (Strike the Blood) 3rd familiar, Al-Maisan Mercury, has strong bites, known as the Dimension Eater that will eat up space and devour anything.
Sayaka Kirasaka's (Strike the Blood) Kōkarin sword can cut through anything by severing the spatial connection, even barriers can't withstand its power.
Sagittarius's (Valkyrie Crusade) arrows can pierce through absolutely anything.
Doryu's (Rave Master) Nightmare Spread is considered an unstoppable attack that even Haru's Runesave can't stop it,