Hello everyone! This idea was inspirated to me by All Out War II and a mod Master of Puppets.
Monsters occupied a well fortified region. It can be whatever: UAC base, medieval castle, hell forstress, astral citadel... Marines should capture this area, but they are limited in reinforsments. All like in MoP, this WAD is intended for it. In the very heart of the base abides evil Mastermind, who controls the defence of hell forces. He can observe whole battlefield with convenient points, gives important orders, activates global traps and even can take part in the battle.
The whole map is divided by sectors, initially all of them except marine start points are under control of monsters. During the game checkpoints can change hands from monsters to marines and back, here is their list.
MARINE START RESPAWN POINT. Initially there are on of them (or two for big maps). It can be the landing ship, landing bot teleporting forces from the orbit, a hell portal - whatever? it depends on the map and authors fantasy. And either from map it depends whether this point can be captured or not. If marines loses all respawn points, they could be reinforced no more. Initially there is only weakest weapon on it (shotgun) and a few ammo. Green armor can also be added for really difficult maps, not more.
FORTIFICATION. The basic control point, give you an example. Two towers guard a narrow rocky valley, a bridge is set across them. Arachnotron pads are at the foot, chaingunners on the bridge. Behind the towers there is a secluded niche where Mastermind can spawn chaingunners. Spawn of arachnothrons processes like this: if the pad is free it goes down and then up with a fresh spidey. If marines capture the fortification, ammo and medikits spawns instead of chaingunners.
BARRACKS. Differs from fortification in the point that it is not supposed for shooting the enemy from the cover. Instead of this a lot of meat (imps, pinkies, mancubi), tons of it are borned there for the openfield battles. For marines again it is ammo and medikits.
FACTORY/LABORATORY. You can ask, where are the Mastermind's monsters from. Obviously, not from the air. He can hire them form resources, which this type of buildings produces. Factory security usually not too big. Capturing it marines not only pulls the plug of the enemy, but takes a new weapon or bun like soulsphere of invisibility. The question about how will be spawned a new types of weapon or ammo: inside the factory itself or on the marine start point we will grant to decide uncle Balance.
TOWER. Very uncommon building. It is tall, powerful and can shell marines from afar with rockets, BFG balls, railguns or like an Obelisk of Light в AOW2. It functions can also be combined with fortification ones. The one main difference is that after marines capturing it the tower loses it artillery functions till the end of the game.
THE PORTAL. What can be done if all around is captured and miserable human are just about to launch the final assault? In that case Mastermind has the last trump card in his sleeve. In the very unsuitable moment a Cyber can come out of the portal and severe punish insolent dudes. But it is not that easy, the power of the portal grows during the game so Mastermind can not summon arch-viles right away. After the summon the power of the portal drops and it need some time to recover. Of cource that luxury is available only on big maps. To destroy or capture the portal is IMPOSSIBLE.
THE CITADEL. The very heart of the base. Here is the Mastermind who make his plots. His room is the trully control center set with monitors with cameras and control consoles. The separate place occupies a huge dynamic base map which indicate what places are under control and what places are captures. Seizure of The Citadel leads to an unconditional surrender of all monsters on the map. The assault should be ended with marines epic bursting into the control room and smearing brains of the Mastermind along the wall (at the normal state he is not stronger than an imp, but once in the game he can get onto his own mech and teleport to the battlefield). Usually the citadel is also the biggest barrack and fortification on the map, the Portal situates in the same building.
Initially there is the Dark Crystal in every building (except the Portal and the Citadel). To capture the building marines destroys it. Where do the crystals produced? May be in factories/citadel? Or will it be a special building - the question is open. To return the building a monster (any) should take a Crystal and bring it to the right place, usually at the most unreachable spot in the building. After death a monster drop it so another one can pick it up or it can be destroyed by a marine. A Crystal can also be discarded so that another monster can pick it. After placing the building takes time to recover and then it is ready.
Every building can be proveded with a respawn marine property. So capturing a new building affords marines to respawn directly in the base. From every point of respawn, except start points, some marine reinforcements tick slowly (one at a minute but not more than appointed maximum).
As you have guessed medikits, ammo and all pickable items can not be found in the "wilderness". Only in the checkpoints and only on capturing. Or may be on corpses of fallen. Upon marine death it LOSES ALL WEAPONS. As in the AoW, some exp points can be introduced.
PS. I'm not mentioned anywhere above that weapons and monsters must be standard. Improvise!
PPS. Now when I told you all you can imagine how difficult it will be to incarnate and test it all.