title explains it all..
Nacht Der Untoten v1.6 (made 2010, updated 6 years ago)
https://www.roblox.com/games/22202224/Nacht-Der-Untoten-v1-6
Blockcraft (bad minecraft copy, but cool to experiment with. made 2010)
https://www.roblox.com/games/25284976/Blockcraft
Assassins creed (most weapons dont do damage, but the flips are fun to mess with and explore the map. created 2010)
https://www.roblox.com/games/34590840/Assassins-Creed
F.E.A.R. (old horror game, made 2010 and still works!)
https://www.roblox.com/games/21140258/F-E-A-R-First-Encounter-Assault-Recon-READ-DESC
What happned!?~*FUUUUUUN*~Done (2008 horror game, crouching is broken but im pretty sure it still works. i got stuck so i couldnt do a full playthrough, btw theres like no checkpoints.)
https://www.roblox.com/games/3850472/What-happned-FUUUUUUN-Done
hope you have fun! if theres any other games you think i should add, tell me! :D