Big worm

The Big worm is a static enemy turret that defends alien nests and attacks players and vehicles at range by spitting corrosive acid. It functions like a ranged spitter but remains stationary and does not chase targets. Big worms rely on high damage, long range and splash effects to protect their spawn areas; they are far more resistant to common small arms than smaller worms and can force players to use heavier ordnance or long-range tactics.

A single Big worm has 1500 health and an attack range of 38 tiles. Its acid projectile fires at 0.65 shots per second, deals 72 acid damage on contact with an area-of-effect radius of approximately 1.75, and creates an acid puddle on impact. The puddle lasts 32 seconds and deals very high damage over time (259 acid damage per second), applies a movement/vehicle speed modifier (40%), and applies a brief slowing/damaging effect for 2 seconds to units crossing it. Placed buildings and tiles do not take damage from the puddles, but buildings and vehicles take normal damage from the acid projectile itself.

Big worms have substantial resistances: explosion resistance 10% with a 30% damage reduction listed, fire resistance 3% with 70% reduction in some contexts, laser resistance about 50%, and physical resistance around 10%. These resistances make them nearly immune to light firearms and make explosives, lasers, or heavy ordnance more reliable options for removal. Worms in general are highly resistant to fire relative to other enemies.

Worm sizes (small, medium, big, behemoth) and their appearance are influenced by the game's enemy evolution factor and map generation. Big worms are typically created by enemy expansion once the evolution threshold permitting them is met and they also appear more frequently further from the player start area.

• Treat a Big worm like a static turret with very long reach: do not expect it to retreat or pursue.
• Acid puddles block and slow movement and deal heavy damage to players and vehicles; avoid lingering in puddles or pathing vehicles through nest centers.
• Use ranged or high-damage ordnance: rockets, artillery, heavy laser setups, or tanks with explosive weapons deal with Big worms more reliably than small arms.
• When clearing nests, kill worms first if possible, or neutralize them from beyond their 38-tile range; cover approaches with shields or vehicles to absorb hits.
• Worm projectiles damage structures directly; build repair and combat plans accordingly when pushing into nest territory.