Survival¶
Endless mode. Enemies spawn continuously, accelerating over time. The player levels up from XP, picks perks, and survives as long as possible. Score is total XP.
Starting conditions¶
- Weapon: Pistol.
- Always available: Pistol, Assault Rifle, Shotgun, Submachine Gun. Additional weapons come from quest unlock state.
- Bonuses: enabled.
- Perks: enabled, manual selection on level-up.
XP and leveling¶
XP required for next level:
1000 + 1000 × level^1.8
Each level-up adds one pending perk pick. The perk menu appears while at least one player is alive and a pick is pending.
Spawning¶
Continuous waves¶
Spawn cooldown decreases by player_count × frame_dt each frame. When
it crosses zero, one creature spawns from a random edge and cooldown
resets to:
500 − elapsed_ms / 1800 (milliseconds, minimum 1)
If the interval is already negative, extra creatures spawn first, then the interval stretches by 2 ms per extra spawn to keep spacing stable.
Milestone waves¶
At certain player levels, scripted waves spawn immediately:
| Level | XP | Wave |
|---|---|---|
| 5 | 13,125 | Two 8-alien rings from left and right |
| 9 | 43,224 | Red boss |
| 11 | 64,095 | 12-spider pack |
| 13 | 88,604 | 4 fast red aliens |
| 15 | 116,619 | 8 spiders, 4 per side |
| 17 | 148,033 | Red ranged spider boss |
| 19 | 182,756 | Splitter spider pack |
| 21 | 220,712 | Two splitter packs from opposite corners |
| 26 | 329,315 | 8 ranged spider bosses, 4 per side |
| 32+ | 484,560 | Shock-capable spider bosses and ranged columns |
Secret weapon handouts¶
Two one-time weapon handouts can trigger in single-player Survival. See Secret weapons for full conditions.
Scoring¶
Ranked by highest XP. The end-of-run record includes elapsed time, kills, shots fired, shots hit, and most used weapon.
Game over¶
The run ends when all players are dead and their death timers have completed.