Base Defense Assault Warning Timeline and Preparation Guide

What this timeline actually tracks

An Assault Event is a random raid around a selected Crafting Bench. It is not a five-tier calendar that automatically advances on particular survival days. The available event types expand as the group reaches progression milestones, so two saves at the same day count can face different threats. Planning around a made-up day table creates false confidence; planning around the warning messages, the selected bench, and the known approach lanes gives the team decisions it can use.

This guide covers the period from the first warning through post-event recovery. It does not predict an exact enemy count, wave duration, or next raid date. Those details can vary by event type and game state. The Assault Events reference is the source of truth for currently documented variants and their progression conditions.

The official event page places the first warning at 4 PM on the afternoon before an assault. Treat that clock time as a notification trigger, not as a guaranteed countdown length. The selected Crafting Bench is not chosen until the later start message appears, which is why the preparation plan separates general readiness from final bench assignment.

Before any warning: make the base recoverable

The most valuable defense is not a specific turret count. It is a layout that can fail in one place without trapping the players or cutting them off from repairs. Keep one clear route from the sleeping and storage area to the Crafting Bench, one route to a safe fallback room, and enough working space to reach damaged deployables with a repair tool.

A Crafting Bench creates the base safe area and prevents ordinary enemy spawning inside its radius while powered. Assault enemies are an exception, and the bench also becomes an event target. The Crafting Bench reference recommends supplying the bench with a battery so that its normal functions continue when facility power is unavailable. Therefore, bench power belongs in the base checklist even when automated defenses use a separate circuit.

Build a simple readiness station near the protected area:

1. Store the appropriate repair items beside the route to the perimeter, not behind a doorway enemies may block.
2. Keep a charged battery reserved for the Crafting Bench or the defense circuit that matters most.
3. Mark the likely approach lanes with ordinary objects while the area is calm, then watch where real enemies enter during an event.
4. Leave a fallback route that does not pass through the primary choke point.
5. Put irreplaceable or expedition-critical items away from the first line of furniture.

The first live assault at a new base is also a survey. The event system chooses a nearby spawn point relative to the selected bench, according to the official event page. Record the direction enemies actually use and adjust the layout after the event instead of assuming every corridor is equally likely.

Afternoon warning: switch from building to staging

When the afternoon warning appears, stop cosmetic construction. The team now has a finite preparation window, but the source does not establish a universal number of seconds. Use a priority order that still works whether the event starts sooner or later than expected.

Do not redesign the whole base during this phase. Packaging or moving the Crafting Bench changes the object around which the safe area and event plan were built. A late move can also leave defenses facing the wrong direction. If the current base is clearly indefensible, the safer response is to reduce what must be protected and prepare an exit rather than attempt a complete rebuild after the warning.

Players who intentionally stay far from the selected bench can delay an assault until they return to a Crafting Bench radius, as documented on the Assault Events page. That behavior is useful for finishing an expedition, but it is not a cancellation. The pending event still needs a deliberate return plan. Do not send one player back alone with the assumption that the raid expired off screen.

Start message: confirm the selected bench

The later "The air feels different..." message is the operational handoff. The event can now select a Crafting Bench, and the documented strategy says the bench closest to a player is chosen; with multiple players, one of the closest benches may be selected. This creates an important co-op rule: stop scattering across multiple bases when the start signal appears.

Use this short confirmation sequence:

1. Call out each player's current location and nearest bench.
2. Identify where the event-specific announcement or first enemy activity is occurring.
3. Move defenders to that bench without dragging unrelated patrols through another base.
4. Assign one person to watch the least familiar approach instead of stacking everyone at the obvious doorway.
5. Keep the retreat path open until the event has actually ended.

If the wrong bench was selected, defend the selected location as it exists. Do not assume enemies will transfer to a preferred base because the group runs away. Protect players first, then the Crafting Bench, then replaceable furniture. A prepared repair cache and clear access lane make an imperfect bench survivable.

Active event: defend information, not a guessed wave count

The official event list contains different enemy groups unlocked by progression. That means a fixed "wave one through wave six" script is not reliable. Watch the current enemies and the route they use. Automatic items in the Base Defense category can support the hold, but no single device substitutes for placement, power, and repair access.

Use three roles even when one player must perform all of them:

Avoid sealing every doorway with a solid wall. Assault enemies can attack deployables and base defenses along their approach, and the team needs a controlled way to engage and repair. A layered route is more recoverable: observation at the outer lane, durable delay at the next point, powered defense where it can be maintained, then a final protected path around the bench.

Do not interpret a pause as proof that the event is finished. The documented end message appears after all enemies have spawned, but enemies may still be alive when it appears. Keep the defensive posture until the nearby area is checked and combat audio has stopped.

Recovery after the end message

Once "The air is normal again..." appears, clear remaining hostiles before opening the base for repairs. Then restore function in this order:

1. Confirm the Crafting Bench still has power and can perform its normal role.
2. Reopen the primary movement path so a second threat cannot trap the team.
3. Repair or replace the barrier that controlled the most-used approach.
4. Restore powered defenses and recharge or swap depleted batteries.
5. Return critical storage and workstations to protected positions.
6. Record the actual approach direction and any blind spot exposed by the event.

The record can be one sign, a short note, or a shared screenshot of the layout. The important outcome is a factual update: where enemies entered, what blocked them, what failed, and what could not be reached. That evidence is more useful for the next event than an assumed universal build order.

Failure diagnosis

Completion condition

The preparation plan is complete when the team can answer five questions without guessing: which bench is likely to be selected, how its power is backed up, where enemies approached last time, how defenders retreat without crossing the choke point, and where repair materials can be reached during damage. The event itself remains random, but those answers make the response repeatable.

See Also

• Power Grid Star Topology
• Defense: Chopinator, Tesla, and Trip Mine
• Beginner Base Defense Setup
• Best Base Locations Tier List
• Shock Trap Base Defense Layout