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Project: Vaccine A
Also known as Project: Vaccine A, project vaccine a, project-vaccine-a
Firewall, vaccine, cleaner... Place various blocks to protect your CPU! Vaccine A is a sandbox defense game, filled with parody of various programs.
Last update
1 Jun 2026
Players now
0
Latest update
Update history
Browse past updates and patch notes for this game.
21 updates
April 2026
- 2.1.3.3 patchnoteBugfixes -Fixed bug that Healing exact frame when you die in millennium bug fight causes glitch win -Fixed bug that x/4 Vaccine A's attack crashes game when it hits encrypted type mob for 5th hit
- 2.1.3.2 patchnoteSystem change -Added progression bar to Millennium Bug Bugfix -Fixed bug that when selected block destroyed, game crashes.
March 2026
- 2.1.3 patchnote2.1.3 update! -CPU bonus Vaccines now gain additional effects when they are near the CPU! You can also increase the CPU bonus range in the Registry Editor. -New feature You can now return to HQ from the Network Card! Al…
December 2025
- New Year update!2.1.2 update! The New Year has arrived! Headquarters is buzzing with New Year preparations!..Hey M, don’t you smell something burning? (New Year event can be played during January!) -And more... 1 design change And 2 bu…
July 2025
- 2.1.1 patchnoteSystem changes -Vaccine C's turret now shoot targeted enemy first -Added modpack icon in gamefile selection window. Hover mouse over it to check what mods applied to it. Bugfix -Defeating Straw hat after Digital Piracy'…
June 2025
- Workshop update!2.1 update! We are back with new 'Modpack' system, and Vaccine V & Perks reworks! -Modpacks Now you can apply various mods! What if your web browser were Firefox..? What if you could have a cute goose..? Or... what if y…
January 2025
- 2.0.1 patchnoteSystem change -Added 'Level up available' UI on network card. Bugfix -Fixed bug that defeating 'Badly Drawn Graphics' and 'You are an Idiot.exe' doesn't unlock new characters
- 2.0 update! We are back with new bosses,#and various major changes! -New bosses 3 new bosses have been added: Badly Drawn Graphics, You are an Idiot.exe and Memory leak! They will randomly appear in place of existing bo…Security
August 2024
- 1.9.1 patchnoteDesign change -Resprite space intruder / Bobble bubble Bugfix -Fixed bug that changing crafting table from converter caused crash.
- World Wide Web update!1.9 update! We are back with new NPC/events and various blocks added!! -New blocks Bookmark and Hyperlink added! Install these new blocks with Web design tool, and quickly navigate to the installed page! New game, 'Bobb…
January 2024
- 1.8.8 patchnoteBalance adjustments -Spaghetto code: delete spawn limit, HP 120->80 -Spaghetti code: max text beam count 10->9 Design changes -Mob found UI resprite -Database UI resprite -Added spaghetti code's text beam effect Bug fix…
Gallery
In-game media
Achievements
Community progression
Top picks from 41 Steam achievements, sorted by player unlock rates.
- The bird flies to GodTerminate Abraxas Virus in Survival45.1%
- Recycle BinEarn total 300 energy using delete in Survival35.5%
- Helo I am a middleskool artistDefeat Badly drawn graphics in Survival34.7%
- Chef's RecommendationTerminate Spaghetti Code in Survival32.7%
- Boss RaidReach 1,000 DPS in Dummy32.3%
- Tag:stuck_in_wallHidden31.6%