Space Marine 2 Siege Mode: Waves and When to Leave

The loop

A squad holds an enclosed area against waves of Tyranids and Chaos. Between waves you spend Requisition on restocking and reinforcement. Waves are not purely killing: objectives appear — powering generators, investigating corpses — and completing the challenges listed in the pause menu accelerates your income. Every five waves you reach an extraction point and choose: leave with everything earned so far, or descend into a new sector with a different faction and harder waves. Rewards improve with depth, and each descent resets the count you have to survive before evacuation is offered again.

The shop

Four categories, and they answer four different problems.

• Consumables — Medicae Stimms, a grenade bundle, five ammo crates, a reusable ammo cache, armour boosters, or a self-revive Relic. Buy these when the squad is bleeding.
• Astartes reinforcements — temporary class buffs, five minutes each: extra melee damage, faster ability recharge, headshot damage, ranged damage, ranged damage mitigation, melee damage mitigation. Cheap, and the correct buy when the squad is alive but under-damaging.
• Astra Militarum Guardsmen — escalating tiers of Cadian troopers, from a few dozen up to eighty. Bodies that soak a wave for you, and the best value on defence objectives.
• Dreadnought — the expensive one. You can donate 50, 100, 250, or all of your Requisition to it; enough donations summons a Dreadnought to fight alongside the squad. The correct buy for a final wave, not an early one.

The wave rewards

Normal pays roughly 60 Requisition at wave 5, a Data bundle at 10, 300 at 15, a better bundle at 20, and 500 at 25. Hard pays substantially more at every checkpoint — around 190 at wave 5 and 1,000 at 25, with higher-quality bundles. Since Hard also throws more Majoris and Terminus enemies at you, the trade is depth against survival.

The weekly goal

Reaching wave 15 once a week pays Accolades — 50 on Normal, 100 on Hard — and you must be in the lobby from the start of the run to the end to qualify. Patch 14 changed the condition from surviving 15 waves to reaching wave 15, which makes it considerably easier to claim: dying on wave 15 now still counts. That single change reframes the mode. If your goal is the weekly, the efficient run is a focused push to 15 rather than a deep descent, and Normal is a perfectly good place to do it. Depth is for the nights you want the challenge.

Atonements

Patch 13 added Atonements: a debuff applied every five waves, chosen at the altar before the run using resources. Choosing your own penalty is better than accepting a random one, and some penalties hurt far more than others in a horde — pick a cost you can play around rather than one that removes your ability to hold ground. For the mode next door, see how Stratagems differ, and for the Operations loop, the mode guide is the starting point.