A hidden background stat that regulates itself based on the player performance.
The higher the agro, enemies will spawn faster, perhaps more numerous, and maybe even with more powerful enemies yet to be seen. Pretty much any way to make the game AI harder could be changed.
Agro slowly decreases over time. The only way to keep it high is to consistently hunt down enemies.
Additional notes could be:
Multiplier bonus for high agro (incremental 1x, 2x, 4x, etc).
Less pigs spawning, making 'shrooms valuable. At present there are way to many shrooms on the maps, and pigs are really easy harvests.
Minimum agro stat could grow over time, forcing players to gain agro even whilst camping. This adds to the challenge.
The higher the agro, enemies will spawn faster, perhaps more numerous, and maybe even with more powerful enemies yet to be seen. Pretty much any way to make the game AI harder could be changed.
Agro slowly decreases over time. The only way to keep it high is to consistently hunt down enemies.
Additional notes could be:
Multiplier bonus for high agro (incremental 1x, 2x, 4x, etc).
Less pigs spawning, making 'shrooms valuable. At present there are way to many shrooms on the maps, and pigs are really easy harvests.
Minimum agro stat could grow over time, forcing players to gain agro even whilst camping. This adds to the challenge.