While not a traditional boss, this mission involves defending Truth's farm from a large-scale police and military assault, acting as a significant defensive challenge.
Phase 1: Initial Waves
The farm will be attacked by police cars and SWAT vans. Use the Minigun (if you have it) or an M4/AK-47 to destroy the vehicles and eliminate the officers. Position yourself strategically to cover multiple entry points. Truth will assist with a flamethrower. Keep an eye on the farm's health bar (represented by the 'weed' health).
Phase 2: Helicopter Attack
Eventually, police helicopters will arrive. Switch to a Rocket Launcher or Heat-Seeking Rocket Launcher to take them down quickly. If you don't have these, an M4 can eventually destroy them, but it's much harder. Prioritize the helicopters as they can inflict significant damage to the farm.
Phase 3: Final Stand & Escape
After several waves, you'll need to get into Truth's 'Mothership' (a psychedelic van) and escape. Drive carefully, as the van is fragile. You'll be pursued by police cars. Use the van's unique ability (if any) or simply outrun them. The mission concludes once you reach San Fierro. Rewards: Unlocks San Fierro, significant story progression.