Add mine switching target requirement. When mine drop count down finish, one widow mine generated in drone line and burrowed. Constantly switching target for this mine to prevent it from activated. Widow mine will self explode after 15 seconds.
Change second base to rich mine with no vespene gas.
Add sentry tower so one can observe enemy coming.
Decrease the amount of mineral in main base and add second base in the lower ground.
Add ramp and hill between second base and zerg spawn location.
Mutalisk will appear after wave 5; ultralisk will appear after wave 7; brood lord will appear after wave 9.
Increase zerg attack, armor level and techupgrade after wave 4 and wave 8.
Attack wave starts at 4 minute for each 1 minutes. Overall 10 waves with 15 minute game time.
Defend waves of zergling attack use Terran units.