My observations about single player in RTS:
People like standalone single player missions with scoreboards - challenges.
Example: Generals mode of Zero Hour. Kodachi Rally in ZK.
People like a list of challenges of increasing difficulty so they feel progression as they nail them.
Example: Cod6 coop commando missions.
Newer RTS players like COOP with AI allies so they don't feel 'alone'.
Before I became a strong MP RTS player, this was always my mentality.
We have a few missions titled things like 2v2, 2v1 that sort of touch on this.
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My idea:
I was thinking that we could expand on those missions and cheaply put out a lot of 'challenge' missions by just having one mission per map on say, 30 maps, named after the map. eg. Coop Challenge 1: Titan Duel. Coop Challenge 2: Deadlands.
All of these are the player and 1+ AI ally against increasingly tough odds on more challenging/AI friendly maps. By the last missions, players would be 2v6 and starting in the middle of the map with AIs around the outside.
The variables would be number of AI on each side, player and ally start locations. Both player and AI could have a few different bonus starting units in each missions (for example, in later missions AI could have defences start positions to prevent glaive rush AI kill. AI could be given a Krow at start, and player could have air defences around base etc since AI knows to retreat damaged units it should use it reasonably well). The goal would be to teach players about different units and situations while providing a structured VS bots single player package.
Important would be to have a scoreboard for each challenge - with the variable being time taken to win (shorter = better).
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Important questions:
Would these be easy to mass produce compared to single player story driven missions?
Would people enjoy them and try to be top of the leaderboards for each mission?
Would it bulk out the single player in a good way?
Would they be fun/interesting enough?