B.B. (Prime)
- B.2 is an Autobot Mini-Con from the Prime portion of the Aligned continuity family.

B.2 (ビーツー Bītsū) is Bumblebee's Arms Micron partner. Bright and cheerful, he's a chirpy little fella.
Fiction
Prime cartoon
- Voice actor: Motoko Kumai (Japanese)
B.2, O.P., and R.A. tried to transform. Perfect Transformation! Enter the Transformers B.2 and R.A. succeeded at transforming into robot mode, but O.P. still struggled. Dark Transformation! Dark Energon Having finally transformed to robot mode, O.P. got R.A. and B.2 to combine with him and form the Star Saber Super Combo Weapon. Rescue Transformation! Fowler in Crisis
B.2 and R.A. got infected by Dark Energon, which gave them black color schemes that they thought were really cool and fashionable. They talked about their new looks during a talk show hosted by Arc, and were annoyed when she said black didn't suit them. Infiltration Transformation! Battleship Nemesis After a long day of being used as weapons, B.2 and R.A. decided to relax and have fun. Mostly they just went manic, with B.2 transforming to gun mode and shooting randomly. Explosive Transformation! Spacebridge Battle
Wearing a jaunty baseball cap, B.2 joined O.P. and R.A. in a radio show and read a postcard from Starscream asking for life advice. Aerial Transformation! Skyquake With O.P. still kind of shaken up after his encounter with MECH, he asked B.2 and B.H. what they could do to make life easier on their larger partners. B.2 suggested they drive the Autobots in vehicle mode; O.P. didn't exactly think this was a good idea. Reckless Transformation! Protect the Dingus! As part of the 10th-episode celebration, B.2 donned a set of Groucho Marx glasses. All-Out Assault Transformation! The Pair of Assassins When Zamu and Gra entered the Arms Micron studio, B.2 really didn't have much to contribute to the scene. Acceleration Transformation! Speed Match!
B.2, R.A., and Arc were ready to make a big announcement... when the walls of the studio fell away, revealing the looming presence of the colossal maw of Gari Robo-kun. B.2 was rightfully terrified. Mystery Insect Transformation! Forest of the Spider Woman! When Arc combined with B.2 and a bunch of other Arms Microns to form "Fire Galaxy Super God Star Arc" and chase away the Decepticon Microns, B.2 was the only one to notice there were two O.P.s in the combination. Phantom Transformation! Skyquake Returns Gora soon returned for a rematch, and B.2 and C.L. watched as she tricked him into forming various combinations instead of fighting. Strategy Transformation! Unravel the Sinister Thread!
In the form of the Star Saber, B.2, O.P., and R.A. attempted to stop the Dark Matter Calibur trio from causing trouble, but were defeated. Adhesive Transformation!? Magnetic Tag Match While their new rivals were asleep, the trio tried to think of a way to defeat them by listing off their Arms Micron abilities, but came up empty-handed. Exploration Transformation! Escape from the Underground The Autobot Microns hosted the same party again for the 20th-episode celebrations, this time with B.2 wearing an afro wig and mustache. Duel Transformation! Quell Cliffjumper's Regrets B.2 and his pals were eventually able to defeat the Dark Matter Calibur... by having the Cosmotector trio do it for them. Friendship Transformation! My Bulkhead
B.2 helped cook mapo energon on the Cooking Arms cooking show by heating the sauce with his gun mode, though it all ended in tears when they got the Star Saber involved and cut up the entire studio. Forbidden Transformation!? Ratchet's Strongest Legend? He spent one day playing Mystery of Convoy with Bumblebee and Raf. One-Shot Transformation! Optimus Prime VS Megatron When a mysterious package arrived, B.2 watched as O.P. and Arc argued whether to open it or not. Giant God Transformation! The Advance of Gaia Unicron After it turned out to contain the Matrix, B.2 witnessed R.A. combine with it into the Matrix Saber, though the sudden change to his friend's personality caused him to wonder if the Matrix was Synthetic Energon. Rivals Transformation! Birth of the Strongest Combination
When O.P. lost his memories, B.2 and R.A. tried to jolt him back to normal by combining with him into the Super Star Saber, but he remained just as confused and referred to B.2 as "Kumai". Forgotten Transformation! Optimus Has Become a Decepticon Introduced to junior Decepticon Arms Micron, Ida, B.2 found her voice and personality adorable and helped her form the Black Widow Claw. C.L. had to keep reminding him that his crush was kinda weird, Ida being a spider. Hopeful Transformation! Aim for Planet Cybertron His memories restored, O.P. tried to trick B.2 and the others into thinking he was still amnesiac for a candid camera segment, but they saw through his prank and tricked him back by pretending not to care. Activated Transformation! The Key to Vector Sigma When Bumblebee lost his ability to transform, he could also not deploy B.2, who was stuck inside his arm. Bored, he called up O.P. and R.A. and asked them to cut open Bumblebee's arm for him, but they wisely refused. Unable to Transform!? SOS Bumblebee Once he was freed, the Microns held a weapon-linking contest to celebrate, though B.2 left midway through after Raf called him to hang out. Brave Transformation! The Surgeon's Decision
Toys
Prime

- Available only with Bumblebee, B.2 transforms from a humanoid robot into a twin-barreled blaster resembling Bumblebee's in-show weapons (which were omitted from the Japanese toy). He has numerous 5mm posts and holes that allow him to combine with other Arms Microns to form any number of "Combo Weapons" and "Super Combo Weapons", such as the Star Saber formed by him, O.P. and R.A.
- B.2 comes out of the package as a bunch of unpainted parts on runners, like a model kit. Extra deco is supplied by customer-applied foil stickers on a sheet he shares with Bumblebee.

- Shining B.2 (Promotional Micron, 2012-06-16)
- Energon crystal: SP Pure
- A translucent-yellow, stickerless (save for his under-Crystal insignia) version of B.2 was given away (only to kids!) at the 2012 Tokyo Toy Show on June 16 and 17 of 2012.
- Shining B.2 was also used in the "Arms Up Challenge" at the Next Generation World Hobby Fair Summer '12, taking place on Saturday, June 30 of 2012. Open only to junior-high-and-younger kids, contestants had to assemble an unassembled B.2 in a speed-run deal. All participants got a Shining O.P. for playing.
- Later, Shining B.2 was given away free as a preorder bonus with Megatron Darkness via Amazon Japan.
- And on July 28, the day of Megatron Darkness's release, Shining B2 was given away as a freebie with the purchase of 3000 yen's worth of Transformers product at six different stores, none of which were taking part in the "Hellflame" giveaway Arms Micron promotion going on that day. Five more stores joined the promotion on July 29.
- And then Shining B2 was the third-place "Megatron Award" in an AVEX Prime DVD online "spot the differences" contest/drawing, limited to 20 winners. How many of this thing did they make?!

- Pure Energon B.2 (Promotional Micron, 2012-11-17)
- Energon crystal: SP Pure
- A clear-blue version of B.2, matching his Pure Energon Crystal's plastic, was available as a giveaway with the purchase of 3000 yen's worth of Transformers Prime product at Japanese ToysЯUs stores. He is intended to combine with Shinign R.A., Pure Energon O.P., and the Matrix Saber accessory to form the Pure Energon Super Star Saber.
- Gatling Bumblebee (Weaponizer, 2012)
- Energon crystal: SP Pure
- A dark gray version of B.2, dubbed B.2 A (presumably the "A" stands for "achromatic"), comes with the Weaponizer-class version of Bumblebee in Japan. This version is not only the most show-accurate coloration for B.2 as Bumblebee's gun, it's also the most to-scale version in relation to Bumblebee.
- Arms Micron Ultimate 5 Piece Set A - Advanced Star Saber (AMW set, 2012-12-28)
- Set ID number: AMW-13
- Energon Crystal: SP Pure
- A red version of B.2, dubbed B.2 R, was part of a five-piece gift set of Autobot-allied Arms Microns, which also included O.P. R, Iro R, R.A. O, and Wuji G. All five can combine to form a gigantic combination weapon, the Advanced Star Saber.
Notes

- B.2 bucked the original naming convention for pack-in Autobot Arms Microns slightly; all of the others in the initial wave were named after the first two English letters of their larger partner's names. "B.2" seems to be a bit of a joke on "BB" (two B's, get it?). As time went on, though, Autobot Micron naming got more and more obtuse, to the point where "B.2" actually made more sense than many others.
- B.2 is the only Arms Micron in Arms Micron Theater who doesn't have the same voice actor as his larger partner, for obvious reasons. He instead shares a voice actor with Raf... for also obvious reasons.
- The B.2 toy was commonly used in TakaraTomy product solicitation images as a stand-in for other Arms Microns whenever imagery of the real ones weren't available.
B.2 Combinations
- Named combination weapons including B.2
- Black Widow Claw
- Buster Rifle
- Eclipse Barrett
- Samurai Sword Mode
- Slash Cannon β
- Star Saber
- Super Star Saber
- Arms Up Modes featuring B.2
- Bulkhead Berserk Mode
- Bulkhead Shootgize Galaxy Launcher
- Bumblebee Striker Mode
- Bumblebee Mechya Uchi Ban Ban Mode
- Bumblebee Mecha Uchi Kidō Type
- Cliffjumper Full Burst Mode (combined with O.P.)
- Optimus Prime Sky Master Mode (requires 2 B.2s)
- Ratchet Destroy Mode (combined with R.A.)




