Servers do not check your CD key! Both multiplayer and singleplayer work perfectly on any CD key. Chimera is compatible with both community patches and should never be disabled. Open Sauce and HAC 2 are incompatible with each other, therefore it is recommended to switch to HAC 2 when playing multiplayer (adds map downloading), and OpenSauce when playing singleplayer (enhances graphics, and some maps require it). Halo CE's latest official version is v1.10 (2014), and has 3 community patches: HAC 2 (2016), OpenSauce v4 (2015), and Chimera (in active development). A collection of every known tweak, fix, mod and patch designed to get the most out of Halo CE for modern PCs in 2019.
