Writing Tense
Keep all articles in the past tense, new or old games. As details develop or things are retconned, we can add more detail later. Present tense and past perfect make reading things more confusing as live developments are going to be very common.
Third Person Omniscient is the main perspective to keep. Objectivity is key, despite what terminals may read about a character's view on things, keep those views to the character's article or to the Quotes section.
Sourcing
Sources should be used as often as possible. Outside of plot synopsis, everything from AI roles to character origins should have a source. As Marathon tells its story in terminal format with wildly different interpretations, things need to be backed up with terminal entries. Also, make sure you understand the context of the terminal before sourcing.
Theorycrafting
Theorycrafting should be kept to a minimum. I know we all like Marathon, but the series' main appeal is piecing things together yourself and reaching your own conclusions. KYT, Gherrit White and Infinity timelines should remain objective as to what transpires directly from the text.
References
References should contain be written as: Game, Mission name, Terminal number
With an embeded link to the corresponding terminal on the Marathon story page.