instead of playing against infinite chicken, which the player can't win against:
suggestion 1:
after there are just 2 teams left (chicken and another team), the player has to destroy a variable # of nests. 100. 1000. if the team opposing the chickens manages to destroy that # of nests, the chickens lose.
suggestion 2:
when there are just 2 teams left (as above) the team opposing the chicken can start building special buildings that decrease the max # of chicken nests.
when the # of nests reaches 0, the chickens lose.
each time that special building is built, the chickens go up in everything. numbers, AI lvl
as with the first suggestion, the player can set up before the match how many nests the special building works against.
suggestion 3:
same as #1, but the chickens spawn white dragons each (variable) # of nests destroyed.
variant: each 10 white dragons spawned, 1 queen spawns.