The Booster v2.0 (ブースターv2.0 Būsutā v2.0) is a jetpack created by Professor Booster, originally designed as an aid to investigate the island. It is the completed version of the Booster v0.8 and one the two prerequisites for gaining entry to Blood Stained Sanctuary.
The Booster v2.0 is comprised of two rectangular objects with rectangular nozzles at the end of each. According to the remastered graphics, the Booster is azure in color, but in the original graphics and in Cave Story 3D it is shown as green.
Assuming the player did not receive the Booster v0.8 from Professor Booster in Labyrinth B, when Quote returns to Arthur's House after exiting the Main Artery, Professor Booster teleports to Arthur's House upon finishing the Booster v2.0. He gives Quote the finished Booster and requests Quote to escape from the island with Sue Sakamoto.
Like the Booster v0.8, the Booster v2.0 requires the player to equip it to Quote in the inventory before using. When equipped, if Quote presses the jump button while in midair, he will boost in the direction that the player inputs. By default, it flies upwards.
Later in the game, Momorin Sakamoto takes the Booster in order to build the rocket. She keeps the Booster until the player interacts with her after the rocket is ready. The player does have the option of neglecting to get it back, but doing so disallows Quote from accessing the Blood Stained Sanctuary.
The Booster v2.0 is also the trigger for entering Last Cave (Hidden) instead of the normal Last Cave. Even if Quote previously entered the normal Last Cave, after he obtains the Booster v2.0, he can only enter Last Cave (Hidden).
When Quote boosts, his velocity immediately jumps to the maximum in-game velocity within the direction he is currently facing. This velocity is maintained until either the jump button is released, the Booster v2.0 runs out of "fuel" or Quote takes damage, all of which cause his speed to be halved.
The Booster v2.0 has enough fuel for precisely one second of boost, after which he must land on the ground or on top of certain enemies in order to boost again.
Quote is also unaffected by gravity as long as he is boosting with the Booster v2.0. As a result, the only possible forms of vertical movement while boosting horizontally are damage boosting off of an enemy and using the Machine Gun.
Quote will boost farther than the normal boost if the player keeps pressing the jump button, causing the boost just to have the speed of the starting boost.
There are three exceptions to the sudden decrease in speed. If Quote lands on the ground while boosting, unless a cutscene is triggered or the Booster v2.0 is unequipped, Quote's velocity remains unchanged. He will remain at the maximum ingame velocity until acted on by an outside force, usually sliding across the ground or turning in midair.
Boosting on the ground can be used as a speedrunning technique. Examples of this are boosting into a hill or onto a level platform. When neither are available, the Machine Gun can be used to direct Quote onto the ground. If Quote jumps at precisely the moment he touches the ground, he will continue flying through the air as fast as before. If done consistently, Quote appears to not slow down.
|General||Mimiga Village • Mimiga • Balrog • Bubbline • Cemetery • Ma Pignon|
|Characters||King • Toroko • Mahin • Jack • Kanpachi • Sandaime • Misery • Little Man|
|Enemies||Egg Fish • Pignon • Gravekeeper|
|Items||Map System • Silver Locket • Arthur's Key • Beast Fang • Mushroom Badge • Booster v2.0|
|Interactive objects||Teleporter • Fireplace|
|Weapons||Polar Star • Missile Launcher • Fireball • Bubbline • Machine Gun • Blade • Snake • Super Missile Launcher • Spur • Nemesis|
|Items||Map System • Silver Locket • Arthur's Key • ID Card • Santa's Key • Chako's Rouge • Jellyfish Juice • Charcoal • Rusty Key • Gum Key • Gum Base • Bomb • Curly's Panties • Puppies • Life Pot • Turbocharge • Clinic Key • Arms Barrier • Cure-All • Booster (v0.8 • v2.0) • Tow Rope • Curly's Air Tank • Medals (Alien Medal • Medal of the Red Ogre) • Whimsical Star • 290 Counter • Teleporter Room Key • Sue's Letter • Mimiga Mask • Sprinklers • Controller • Mushroom Badge • Ma Pignon • Little Man • Iron Bond • Beast Fang • Prinny Cap|