Problem: Plan §3.7.1 claims 65-80% combat density for 2-player matches,
but actual testing showed 0% combat deaths. Zone killed all bots before
they could fight.
Root cause:
- Spawn radius 50% (10 tiles from center) put bots too far apart
- Zone shrink step 2 tiles/turn was too fast
- Bots died to zone before reaching each other
Solution:
- Reduce 2-player spawn radius from 50% to 10% (~2 tiles from center)
- Reduce zone shrink step from 2 to 1 tile/turn (slower zone)
- Bots now spawn close enough to reach safe zone and fight
Results:
- Before: 0% combat density (all zone deaths)
- After: 100% combat density (2 deaths per match across 20+ test matches)
- Tested against: swarm/gatherer, hunter/rusher, guardian/random
Updated TestSpawnRadiusOutsideZone to TestSpawnRadiusWithinReach to
reflect the new design (spawn within reach of safe zone, not outside).
Closes: bf-1jya