The Lost Fullbottles are variants of Fullbottles, a sample bottle-like devices in which contain purified Nebula Gas. Unlike the original 60 Fullbottles that were created from the Pandora Box, the Lost Fullbottles are artificial in nature.

The Lost Fullbottles are also compatible with the Last Pandora Panel, a sixth and final panel of the Pandora Box created from placing the Evol Trigger with all 60 regular Fullbottles placed in each of the regular five panels. The Lost Fullbottles with the black Pandora panel is capable of defying the laws of physics, such as giving the user ability to warp travel.

Lost Smash

Some Fullbottles are used to create Smash, monsters who are humans who mutated from exposure to the Nebula Gas. There are also the Lost Smash, a type of Smash created from the Lost Fullbottles, described as "final forms" for Smash.

Originally, a Lost Smash is created when a human is injected with a heavy dose of Nebula Gas while fusing with two Clone Smash. This has the side effect of the user becoming more aggressive and easier to control.

Foundation X has updated the development of Lost Fullbottles by using the Pandora Box's energy. As a result, a person can alternatively transform directly into a Lost Smash without the need for two Clone by using a Black Lost Fullbottle. Unlike those made using the former method, these Lost Smash are in complete control of themselves.

As of now, six out of ten Lost Fullbottles are used to create Lost Smash. Five of them are former members of Dragon Keepers' battalion division, as after the Dragon Keepers' dissolution from their defeat at the hands of Vanguard Outsiders, Foundation X has captured them and put them under experiments, exposing them to Nebula Gas where they were discovered to have Hazard Levels and were compatible with the Lost Fullbottles.

As for the other one, the said CD Lost Fullbottle, was compatible with a Mage in which Foundation X have learned to be from the Four Founding Mage Families, in which both Tohsaka and Matou.

CD Lost Smash

Motif: CD, UV light

Possesses superhuman agility and CD-based projectile generation. Also later displayed rainbow-colored light generation and attack reflection.

Current User: Sakura Matou

Given the CD Lost Fullbottle has recently discovered to have high compatibility with Mages with high amount of Magic Circuits. Originally, Rin Tohsaka was the ideal candidate, but later research has discovered that her sister, Sakura Matou, is shown far more compatible due to her Imaginary Element: Hollow. Furthermore she has displayed that she does not require Clone Smash to transform, and has full control over her transformation without any side effects.

Castle Lost Smash

Motif: European castle

Possesses great defensive ability and energy projection.

Current User: Kai Shion

Due to his combat skills and aggressiveness, Shion was compatible with the Castle Lost Fullbottle.

Stag Lost Smash

Motif: Stag beetle

Possesses great swordsmanship with blades.

Current User: Eigen Urabe

Due to his combat skills and his expertise in gadgets and weaponry, Urabe was compatible with the Stag Lost Fullbottle.

Owl Lost Smash

Motif: Owl

Possesses superhuman speed and flight.

Current User: Angelica Yukino

Due to her combat skills and her agility, Yukino was compatible with the Owl Lost Fullbottle.

Scissors Lost Smash

Motif: Scissors, Pteranodon

Possesses scissor-like blades and projectiles.

Current User: Renren Akebayashi

Due to her combat skills and intuition, Akebayashi was compatible with the Scissors Lost Fullbottle.

Zebra Lost Smash

Motif: Zebra

Possesses superhuman strength and shockwave generation.

Current User: Yamato Kurusu

Due to his high agility, Kurusu was compatible with the Zebra Lost Fullbottle.

List of Lost Fullbottles

Cobra Lost Fullbottle - Contains elements taken from a king cobra and is adaptable to Transteam system.

Bat Lost Fullbottle - Contains elements taken from a wild bat and is adaptable to Transteam system.

CD Lost Fullbottle - Contains elements taken from an optical recording medium. Recent experiments led to discovery that this particular Fullbottle is highly compatible with a Magus.

Castle Lost Fullbottle - Contains elements taken from an European castle and generate human beings to be more combative.

Stag Lost Fullbottle - Contains elements taken from a stag beetle and generate human beings to be more combative.

Owl Lost Fullbottle - Contains elements taken from an owl and generate human beings to be more combative.

Zebra Lost Fullbottle - Contains elements taken from a zebra and reflects African zoology.

Scissors Lost Fullbottle - Contains elements taken from a pair of scissors and proven effective in stimulating human ambition.

Hammer Lost Fullbottle - Contains elements taken from a sledgehammer. Is still under experiments.

Spanner Lost Fullbottle - Contains elements taken from a wrench. Is still under experiments.