doom 3 the videogame

hey actually this is the toughest game to end but playing using cheats is a better idea so..in the end the big evil will attack and the best way to destroy it is to collect the awesome weapon and will come in the last levels which will be activated by collecting the souls may be four or five its the strongest weapon to kill ..so if u want the cheats the here are they: "for god mode -type "god" for all the weapons including the last spirit weapon-"give all" and i ll tell u the menu or keys to activate that dialogue box later as i have forgot that..ok..