Valheim Base Defense and Raid Guide — Walls, Moats, Spikes, and Counter-Tactics

How Valheim Raids Work

Valheim raids are scripted events that spawn enemies near a player's base. They are triggered by progression milestones — primarily boss kills — and become more dangerous as you advance through biomes. The first time you defeat Eikthyr, the boar raid becomes possible. Defeat The Elder and you unlock the troll raid. Bonemass adds skeleton waves. Moder adds drake raids. Yagluth adds fuling raids. Each progression step makes your existing base more vulnerable to new threats.

Raids do not happen on a fixed timer. They are weighted probability events tied to time spent at a base, with a cooldown between events. The longer you play in one location after triggering a raid type, the higher the chance the next raid will occur there. A raid event is announced by a warning message and ominous music — you have a brief window to grab weapons, position defenders, and prepare before enemies spawn at the edge of your base zone.

Defending a base means designing for the worst expected raid given your progression. A Meadows-only base needs minimal defenses. A base where you regularly process Black Metal and run between Plains and Mistlands needs full stone walls, a moat, and an interior killbox. Mid-progression bases that have not been upgraded to match current boss kills are where most catastrophic raid wipes happen.

Raid Types Reference

Wall Selection by Biome Progression

Walls are the first layer of defense and the easiest to upgrade. Wood walls handle Meadows and early Black Forest threats but fall to Trolls in seconds and burn from Fuling torches. Reinforced wood holds up to Greydwarf raids but still loses to Trolls. Stone walls are the universal answer from Bonemass-era onward — they resist Troll smashes, Fuling Berserker swings, and most raid pressure indefinitely.

Stone walls require a Stonecutter (crafted after Bronze and stone access) and consume Stone in significant quantities. Build the Stonecutter near your base, then quarry stone from any rocky cliff or mountainside. A complete stone perimeter for a medium base takes a few hours of stone gathering — invest the time once and the defense pays off for the rest of the playthrough.

Iron-reinforced sections (using Iron beams to brace large walls) and Marble-tier construction (using Black Marble from Mistlands) are largely cosmetic and structural rather than defensive — they let you build taller, more elaborate structures but do not significantly outperform stone for raid defense. The single biggest defensive upgrade in the game is the wood-to-stone wall transition.

Wall Type Comparison

Verdict: The meta defense is a raised earth wall (hoe-raised dirt) topped or backed by a stone wall, with sharpened stake walls on the outer face. Earth walls are nearly invulnerable to attackers and cost only dirt and stamina. Stone provides the structural perimeter for buildings and aesthetics. Stake walls add damage to anything that tries to climb. This stack is virtually impenetrable to any raid type in the current game.

Moats — The Definitive Anti-Raid Tactic

A moat is a wide, deep trench dug around the base perimeter using a Pickaxe. Most Valheim raid enemies cannot path across a moat that is at least 4 meters wide and 4 meters deep — they wander to the edge, fail to find a route, and either despawn or get sniped from your raised platforms. The moat is the single highest-impact defensive structure in the game.

Build the moat with a Bronze (or higher) Pickaxe by digging in a continuous trench around your base. Make it wide enough that no enemy can leap across (Wolves and certain late-game enemies have leap distance you must account for) and deep enough that climbing out is impossible. Pile the excavated dirt into a raised earth wall on the inner edge for double defense — the outer trench plus the inner raised wall.

Access into the base goes through a single drawbridge or a controlled gate. Wood drawbridge mechanics let you lower the bridge to enter or exit and raise it during raids. Some players use a removable section instead — break the bridge piece, walk in, rebuild. Both work; the drawbridge is faster but more vulnerable to Trolls (which can destroy the bridge mechanism if it is exposed).

Moat Construction Step-by-Step

1. Plan the perimeter — mark with stakes or torches where the trench will run. Account for at least 10-15 meters of buffer between the trench and key structures.
2. Use a Bronze (or better) Pickaxe to dig in a continuous loop. Bronze is the minimum tier that hits earth fast enough for a reasonable build time.
3. Aim for 4 meters wide and 4 meters deep. Wider for late-game raids (Wolves can leap), deeper to prevent any pathing solution.
4. Pile the excavated dirt into a raised inner wall — this is your earth wall, and it doubles your defensive value for free.
5. Add a single drawbridge or controlled gate as your only entry point. Make it the most defensible position in the perimeter.
6. Top the inner earth wall with stake walls or a stone wall for aesthetics and additional projectile damage to attackers.
7. Build raised wood platforms inside the perimeter for ranged defenders to shoot from during a raid.

Workbench Coverage and Hostile Spawn Suppression

Valheim suppresses hostile spawns within a radius of any built Workbench. This is the secret weapon of base defense — by placing Workbenches strategically around your base, you can prevent enemies from spawning inside or immediately adjacent to your walls. Raid events still spawn enemies at the edge of the player-zone, but ambient spawns (which can sneak up while you build) are blocked entirely.

Plan workbench coverage as a grid: place Workbenches at each corner of your perimeter and at intermediate points to ensure no spot inside your walls is more than the suppression radius away from a bench. The radius is roughly 20 meters — close enough that 4-6 Workbenches cover a medium-sized base completely. Cover them with small roofs so they do not wear out from rain.

Workbench coverage does not stop raid spawns or wandering enemies that path in from outside. For raid defense, you still need walls, moats, and active defenders. But workbench coverage eliminates the worst-case scenario where a Greydwarf spawns inside your base at night and chips at your wood structures while you sleep.

Counter-Tactics by Raid Type

• Greyling / Greydwarf horde — wood walls hold initially; finish with sword sweeps from raised platforms; campfire perimeter discourages spawns near walls.
• Troll raid (after Elder kill) — never melee in open ground; bow from a high stone platform with Wood or Bronze arrows; troll-spike rings break the troll combo when they get close to walls.
• Draugr swamp raid (after Bonemass) — stone walls hold; bow Draugr archers first; Iron Mace for melee finish; bring poison resistance mead if Blobs spawn.
• Drake raid (after Moder) — roof the base with sloped wood or stone to block frost breath; bow drakes from cover; frost resistance mead helps if you take chip damage.
• Fuling raid (after Yagluth) — stone walls + moat is mandatory; Atgeir sweeps for Fuling packs; bow Fuling archers and Berserkers from raised platforms; Padded armor for defenders.
• Seeker raid (after Queen, if Mistlands-adjacent) — Stagbreaker AoE for Tick clusters; bow Gjall before they detonate near walls; Bonemass Power active during fight.
• Ashlands-tier raid (if Ashlands-adjacent) — full stone fortress; Fire Resist Mead active; Flametal weapons for defenders; pre-clear Volture flocks before the raid lands.

Defensive Structure Cost vs Value