The Last Shelter Mission 4 Guide
Mission 4 unlocks a new upgrade for Heavy Weapon. This is useful against Red Armored Beetle where Rapid-Fire Minigun lacks of armored-piercing bullets. Start by circling your base with multiple Rapid-Fire Miniguns. Start building Heavy Weapon as Armored Beetle arrives on Wave 5. Upgrade your Rapid-Fire Miniguns to cope with the growing masses of weak bugs. Reserve Bomb Air Support at Wave 6 where large swarm of Armored Beetles tries to punch through your defenses. Have all Heavy Weapon max upgraded to cope with Armored Beetle invasion from all entrance at final wave.
Mission 4 Final Layout
Mission 4 Playthrough