Just in case our esteemed mod-devs are short on ideas, I'll just leave these here:
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Monster madness- Every second, commanders spawn a basic chicken next to them
- You get 1 or 2 metal and energy every time one of your chickens does damage to an enemy unit or structure
- Buttons exist to upgrade chickens HP, attack, speed, spawn rate (costs metal+energy)
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Team chicken- Each team automatically gets a chicken ally (spawns roost and has waves as normal)
- Buttons exist to upgrade chicken tech progress, wave frequency, queen stats (costs metal/energy)
- Roosts supply less resources to their team than in standard chicken mode
- Win by killing queen or other team
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Air drop- In addition to or instead of mexes, there is randomly located wrecks of increasing value that drop out of sky, and must therefore be fought over
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3-team and 4 team Zero-Wars maps- Waves targets random or alternating enemy team
- Could autogenerate depending on number of teams, similar to autogenerating FFA maps