Base Defense Assault Event Timeline and Preparation Guide
Complete timeline of assault events in Abiotic Factor — wave composition, spawn intervals, difficulty scaling, and how to prepare your base for each phase.
Original base-building route
Summarize the guide decision flow without adding factual claims. Source basis: the references listed on this page, checked for game version 1.4. This original planning diagram is not to scale and is not copied game or wiki media.
The Problem
Your base got flattened by an assault event you did not see coming. No defenses, no plan, no warning. Everything you built is rubble and you are starting from scratch.
The Solution
Assault events follow a fixed schedule tied to your in-game day count. The enemies, wave count, and difficulty scale in tiers. Know the timeline, build defenses before each threshold, and you will never lose a base to an assault again.
Assault Event Schedule
Events trigger based on your survival day count. Each tier escalates in wave count, enemy strength, and warning time.
| Day Range | Tier | Name | Warning | Waves | Duration |
|---|---|---|---|---|---|
| Day 5-7 | 1 | Scout | 120s | 2 | 3 min |
| Day 12-15 | 2 | Raid | 90s | 3 | 5 min |
| Day 20-25 | 3 | Assault | 60s | 4 | 7 min |
| Day 30-35 | 4 | Siege | 60s | 5 | 10 min |
| Day 40+ | 5 | Purge | 45s | 6 | 12 min |
After Day 40, Tier 5 Purge events repeat every 8-12 days with no end. They keep coming until the save ends.
The warning timer starts with a siren and on-screen alert. That countdown is your prep window. Everything you do during the warning — repairing walls, placing Trip Mines, topping off batteries — determines whether you survive.
Wave Composition by Tier
Tier 1 — Scout (Day 5-7)
| Wave | Enemies | Count | HP Each | Threat |
|---|---|---|---|---|
| 1 | Pest Creatures | 5-8 | 30 | Minimal |
| 2 | Pest Creatures + 1 Mutant Pest | 6-10 + 1 | 30 / 80 | Low |
Pests die to two Pipe Club swings. The Mutant Pest in wave 2 takes 4-5 hits. A single wall segment between you and the spawn direction is enough. This is a warmup.
Tier 2 — Raid (Day 12-15)
| Wave | Enemies | Count | HP Each | Threat |
|---|---|---|---|---|
| 1 | Pest Creatures | 8-12 | 30 | Low |
| 2 | Mutant Pests | 4-6 | 80 | Moderate |
| 3 | Order Scout + Pest Swarm | 1 + 8-10 | 200 / 30 | Moderate |
The Order Scout in wave 3 introduces ranged attacks. It fires from behind the pest swarm. If you are standing in the open fighting pests, the Scout picks you off. Build cover or fight from behind a wall with a gap to shoot through.
Tier 3 — Assault (Day 20-25)
| Wave | Enemies | Count | HP Each | Threat |
|---|---|---|---|---|
| 1 | Mutant Pests | 8-10 | 80 | Moderate |
| 2 | Order Scouts | 3-4 | 200 | High |
| 3 | Order Soldiers | 2-3 | 400 | High |
| 4 | Order Soldier + Heavy | 2 + 1 | 400 / 600 | Severe |
This is the first real skill check. The Order Heavy in wave 4 has 600 HP and a shield. Manual combat alone cannot handle this many enemies across four waves. You need Chopinator turrets covering the approach. Without automated defenses, most players lose here.
Tier 4 — Siege (Day 30-35)
| Wave | Enemies | Count | HP Each | Threat |
|---|---|---|---|---|
| 1 | Order Scouts + Mutant Pests | 4 + 10 | 200 / 80 | High |
| 2 | Order Soldiers | 4-5 | 400 | High |
| 3 | Order Heavies | 2-3 | 600 | Severe |
| 4 | Breach Team (explosive) | 2 | 300 | Critical |
| 5 | Elite Soldier | 1 | 1000 | Critical |
Breach Team enemies are the new threat at Tier 4. They ignore your turrets and run straight for walls. They plant explosives that detonate after 3 seconds and blow open wall segments. Kill Breach enemies on sight. If they reach your walls, the hole they create lets the rest of the wave pour through.
The Elite Soldier in wave 5 has 1000 HP and heavy armor. Focus fire from multiple turrets or a Deatomizer. Do not try to melee this enemy.
Tier 5 — Purge (Day 40+)
| Wave | Enemies | Count | HP Each | Threat |
|---|---|---|---|---|
| 1 | Mixed Scouts + Pests | 15+ | 30-200 | High |
| 2 | Soldier Squad | 5-6 | 400 | Severe |
| 3 | Heavy Squad + Breach | 3 + 2 | 600 / 300 | Critical |
| 4 | Elite Soldiers | 2-3 | 1000 | Critical |
| 5 | Anomaly-Infused Enemies | 3-4 | 500 | Critical |
| 6 | Commander Unit | 1 | 1500 | Extreme |
Tier 5 is endgame. The Commander Unit in wave 6 has 1500 HP, a shield, and calls in reinforcement spawns. Anomaly-infused enemies in wave 5 have elemental damage that bypasses armor partially. You need a full defense grid, endgame weapons, and ideally a co-op team of 2-4 players.
Defense Requirements by Tier
Build these defenses before the day threshold hits. Not after the siren sounds.
| Tier | Minimum Defenses | Recommended Defenses |
|---|---|---|
| 1 | 1 wall segment + melee weapon | Pipe Club, 2-3 basic walls |
| 2 | Walls + Energy Pistol | 3-4 wall segments, Energy Pistol, cover position |
| 3 | Turrets + full wall perimeter | 2 Chopinators, reinforced walls around base |
| 4 | Turrets + Tesla Coils + backup power | 3 Chopinators, 2 Tesla Coils, Carbon Battery |
| 5 | Full defense grid | 4+ Chopinators, 3+ Tesla Coils, Trip Mines, Quantum Battery |
Defense Placement Strategy
Enemies approach from the closest entry point to your base. They do not spawn randomly. They pathfind to the nearest opening.
Step 1: Identify chokepoints. Find the 1-2 corridors or doorways enemies must pass through to reach your base. Most base locations in the facility have natural chokepoints — hallways, doorframes, stairwells.
Step 2: Wall the chokepoints. Place reinforced walls across each approach. Leave a single gap per chokepoint — just wide enough for enemies to funnel through one at a time.
Step 3: Turrets behind walls. Chopinators placed behind walls shoot through the gap. Enemies funneling through the opening walk directly into turret fire. Place turrets 3-4 meters behind the gap so enemies cannot reach them before dying.
Step 4: Tesla Coils at secondary entrances. Tesla Coils deal 45 damage per tick in a 4-meter radius. Place them at any secondary approach where enemies could bypass your main funnel. One Tesla Coil kills Pest Creatures in two ticks and staggers Mutant Pests.
Step 5: Trip Mines as failsafe. Place Trip Mines 2 meters behind your wall gaps. If a Breach Team blows open a wall segment, the enemies rushing through hit the Trip Mine line. Each mine deals 150 damage in a 3-meter radius. Space them 5 meters apart to avoid chain detonation wasting coverage.
Power Budget for Defenses
Every turret and coil draws power. Running out of battery mid-assault shuts down your entire defense grid.
| Defense | Power Draw | Battery Type | Runtime |
|---|---|---|---|
| Chopinator | 5 power/min | Carbon Battery (500) | 100 min |
| Tesla Coil | 8 power/min | Carbon Battery (500) | 62 min |
| Trip Mine | 0 (passive) | None | Until triggered |
| Spotlight | 2 power/min | Basic Battery (100) | 50 min |
For a Tier 4 Siege defense (3 Chopinators + 2 Tesla Coils), you need 31 power/min. A single Carbon Battery lasts about 16 minutes — enough for one event. A Quantum Battery (2000 capacity) covers multiple events without swapping.
Always keep a charged backup battery in a crate within 5 meters of your power grid. Swapping a dead battery during the warning period takes 3 seconds. Swapping during wave 4 while enemies are inside your base takes forever because you are also dodging.
Repair Priority Between Waves
Waves have a 15-30 second gap between them. Use that time wisely.
| Priority | Action | Time Cost |
|---|---|---|
| 1 | Repair breached walls | 4-6 seconds per segment |
| 2 | Replace destroyed Trip Mines | 2 seconds each |
| 3 | Heal yourself | 1-2 seconds (syringe) |
| 4 | Reload weapons | 2-3 seconds |
| 5 | Reposition turrets | 3-5 seconds |
Do not repair cosmetic damage. A wall at 30% HP still blocks pathing. Only repair walls that are fully broken, because a hole in the funnel means enemies bypass your turrets entirely.
Common Mistakes
| Mistake | Why It Happens | How to Avoid |
|---|---|---|
| No defenses before Day 5 | Did not know assaults start that early | Build at least 2 walls by Day 4 |
| Turrets placed in the open | Assumed turrets survive on their own | Always place behind walls; exposed turrets get destroyed in 2 hits by Order Soldiers |
| Single battery for entire grid | Did not calculate power draw | Keep a backup battery within arm's reach |
| Ignoring Breach Team enemies | Focused on the biggest HP target | Kill Breach enemies first; wall explosions end runs |
| Repairing during a wave | Panicked after wall broke | Wait for the wave gap; fighting and repairing at once gets you killed |
| No backup melee weapon | Primary weapon broke mid-fight | Keep a Pipe Club in your hotbar as emergency fallback |
See Also
Sources & References
Wave composition from wiki assault event pages, timing data from community stopwatch tests, defense strategies from Steam and Reddit.
Editorial contribution
Assault wave data compiled from community testing, wiki event pages, and multiple recorded defense runs across different base locations.
- abioticfactor.wiki.gg: Assault Events →
- abioticfactor.wiki.gg: Defenses →
- abioticfactor.wiki.gg: Base Building →
Sources support factual claims. Route choices, comparisons, and recovery guidance are editorial synthesis and may change with game updates.
Author
The editorial desk maintains source-backed Abiotic Factor route notes, item checks, and practical decision guides.
About our editorial team →