Half-Life Decay New PS2 Secret Cheat Konami Code for Unlocking all Misions including Xen Attacks 

Tutorial Video for the half life expansion for the ps2: Decay, which hasnt really been discovered yet but its nowhere else on youtube or even almost the internet so im showing it here. Very useful because thanks to it you can unlock the extra mission without having to get all As in the mission ranking (for ps2), on Pc theres also a different alternative to doing that and the general method.