Base Defense Strategies: Moats, Walls & Spawn Suppression Guide

Why Base Defense Matters in Valheim

A beautiful longhouse means nothing if a pair of Trolls can flatten it in three swings. New players ignore base defense until it costs them everything; veterans obsess over it until their bases become fortresses.

How raids work

Every 46 minutes of real time there is a 20% chance of a raid. Which raid you face depends on your boss progression: Greydwarf hordes after Eikthyr, Trolls after The Elder, and it escalates from there.

Raids only trigger when you are within 40 meters of at least 3 base structures, so a lone Workbench in the wilderness won't attract trouble.

The good news: layered defenses can make your base nearly untouchable, and the most effective one costs nothing but time with a Pickaxe and Hoe.

Terrain Defense: The Most Powerful Tool You Have

Creatures cannot dig through terrain. Raised earth and dug trenches are impenetrable to every ground enemy, from a Greyling to a rampaging Troll. That makes terrain the undisputed king of base defense.

Moats and trenches

Dig a trench around your base with a Pickaxe, about 2 to 3 meters deep, with a sheer vertical face on the inside edge. Most creatures won't jump down from ledges (Fenrings and Blobs are the notable exceptions), so even a modest pit is an impassable barrier.

Tidy the edge with the Hoe

Use the Hoe's Level Ground to tamp down the inner edge into a clean rampart. It copies the height under your feet, so stand at the height you want; hold Shift to target the height of the terrain you point at instead. This saves Stone compared to raising ground manually.

Raised earth walls

Raise Ground costs 4 Stone per use and creates terrain enemies can't break. A raised rampart inside your moat creates a height difference nothing short of a flying enemy can cross. Veterans raise terrain 2 to 3 meters above natural ground and top it with Stakewalls.

Never repair again

Stone walls, Stakewalls and even metal structures can be broken by persistent enemies, but the ground is permanent. The time spent terraforming pays off many times over compared to rebuilding shattered walls after every raid.

Built Defenses: Walls, Stakes and Structures

Terrain is king, but built defenses protect entry points, funnel enemies and deal passive damage. The comparison table below lists their stats.

• Roundpole Fence: the cheapest option, but only good for corralling tamed animals. Most enemies chew through it in seconds.
• Stakewall: your first real defensive wall. It doesn't decay in rain, making it ideal for perimeters, and holds up against most early and mid-game threats. It deals no contact damage.
• Sharp Stakes: the offensive option, damaging and knocking back anything that touches them.

Sharp Stake rules

They lose 34 durability every time they deal damage, so treat them as consumable. They must sit on dirt, draw aggro from nearby enemies and refund nothing when destroyed. Place them in front of Stakewalls or at the bottom of your moat.

Blobs and Stakewalls

Blobs can barely jump a Stakewall on level ground. In the Swamp, always set Stakewalls on a slight rise so they can't hop over.

Spawn Suppression: The Invisible Shield

This separates good bases from great ones. Workbenches, Campfires and other player structures create a zone where hostile creatures cannot spawn, raid enemies included. If suppression blankets the whole raid area, the raid triggers but enemies have nowhere to appear: you see the message, hear the horn, and nothing happens.

Spacing Workbenches

A Workbench has a 20-meter build and suppression radius; select it in the Hammer menu to see the white circle. Because the zones are circles, a 40-meter grid leaves diamond-shaped gaps at the corners. Space Workbenches no more than 28 meters apart: a square about 28 meters on a side is the largest that fits inside a 20-meter-radius circle.

Mind the third dimension

The suppression area is a sphere, not a cylinder, so there can be gaps just above ground even when the circles look complete. Overlap generously and use torches on walls and Workbenches on upper floors to plug them.

The sprawl approach

Build a large base with workshops, forges, campfires and torches spread throughout. As it grows, the overlapping zones cover so much ground that raids simply fizzle out. One veteran discovered this by accident after building an entire city: raids kept triggering, but nothing ever appeared.

Understanding Raids: The Main Events and How to Handle Them

Defeating a boss both unlocks harder raids and disables easier ones. Raid enemies spawn 40 to 80 meters from you in hunt mode: always alerted, and aware of where you are within 200 meters.

Raiders want you, not your base

Raid mobs only target structures when they can't pathfind to you. When a raid starts, run outside your walls and fight away from your buildings. If they start swinging at structures, grab their attention with a ranged attack and kite them away from anything you care about.

Advanced Defensive Techniques

Once you have the basics down, there are several clever techniques that experienced players use to make their defenses even more effective.

Jump Gaps

Gates and doors can be destroyed, but a gap in your wall that you can jump across cannot. Build a narrow gap in your perimeter that is wide enough for a player to jump but too wide for most enemies to cross. This gives you a maintenance-free entrance that never needs repair.

Gangplank Traps

Build a narrow walkway above a pit with Campfires at the bottom. Enemies following you walk onto the gangplank, fall into the pit, and take damage from the fire below. Loot drops down to you. This is especially effective against weaker enemies like Greydwarfs and Skeletons.

Water Gates

Place gates in water to block enemy movement. Enemies cannot attack structures that are submerged, so a gate in water becomes an indestructible barrier. You can open the gate to let boats through when needed.

Terrain Shooting Platforms

Use the Hoe to raise terrain directly beneath you while standing on it. This creates a pillar you can stand on to rain arrows down on melee enemies below. You need a nearby Workbench for this to work, but it creates a quick, indestructible sniping position during raids.

Low Invisible Barriers

On flattened terrain, placing objects roughly 0.5 meters tall (like half-buried reversed stairways) creates barriers that human-sized enemies cannot walk over but will not recognize as attackable structures. They just get stuck. For Trolls, overlapping 45-degree Wood boards in different directions creates hedgehog-style obstacles that block pathing without drawing attacks.

Fighting During Raids: Combat Tips

Even with perfect defenses you will sometimes need to fight. Build the habit: when a raid triggers, go outside your walls and engage away from your structures. Give raiders a clear path to you rather than letting them smash through walls to reach you.

The Troll raid ("The ground is shaking")

Pierce is your best friend: spears, arrows and Atgeirs all deal Pierce, which Trolls are weak to. The Atgeir's spin attack staggers Trolls reliably at level 3 or higher with decent Polearms skill; follow each stagger with regular attacks for a stunlock. If two Trolls appear at once, pick one off with a bow before meleeing the second.

How many Trolls to expect

• Up to 2 Trolls are active at once.
• New ones spawn every 20 seconds during the 80-second event.
• Killing one lets a replacement spawn while the timer runs, so you can face 6 to 7 in total.

Overwhelmed? Keep running. The timer runs while you stay in the area, and once it expires the remaining enemies wander off.

Flying raiders

Later raids bring flyers that ignore ground defenses. The Drake raid (after Bonemass) forces a freezing environment, and the Bat raid can spawn up to 10 Bats. A bow is essential for both. Carry Frost Resistance Mead for Drake raids and keep tamed animals roofed.