i have thought of this in the past and i came up to only 1 thing. HAlo. 3 factions, Flood,Human, and covenant. now ill explain how each would work the flood the flood starts out with a builder that builds the main flood. and thats what they would do, make buildings that made the main flood as thier onltyy unit, nothing more. then with your main flood you could go out and attack the humans and covenant, they would do medium-high damage with little armor,so overwhelming your enemies is key. then once your flood gets close enough to attempt a takeover move. then if they are successful, that hunter,elite,spartan etc would be on your side. thier main resource would be blodd, obtained by a steady stream of hosts. humans this side is has thier infantry,marines.ranged,marines with sniper rifle. heavy infantry, marine with rocket launcher. air,dropships. transport.jeeps. tanks,scorpion. and then the spartans! the spartans would be like a super marine, cost more,better damage/armor and could further specialize in either ranged unit,infantry, or anti tank, these upgrades would also cost additional resources. and 3 buildings, the bartracjks, where all marines are made, autoshop,m where all veichles are made, then The Lab, where all spartans are made. special units, captain keyes,master chief,etc, avalible in campaign. thier main resource is ammunition,collected by ammo boxes thoughout the map. covenant infantry,grunts. ranged,jackals. anti tank, brute. spartan equivilant, elite. then their dropship and babnshee as air,ghost as transport, and wraith for tank. they also have morale, whichn increases performance, generated by the prophets. they have 6 buildings, 1 for each of thier units except for the veichles which are made at the autoshop of thiers. thier main resource is plasma. collected at plasma wells found in the map. now there would be no pop cap, and with the humans and covenant, certain units like spartans and hunters would have increased resistance against the flood. currently there would be no space battles but if there was i wouklld incorporate thier respective battklleships, with the flood using stolen ships in space. so how do you like it? i havent really fine tuned the detaiils, now if i could just buy the rights..... and if i didnt make this clear, the unit type (ranged,infantry etc.) is followed by the unit, for all of ytou who are confused