TL;DR – Key Takeaways
- You start with only one weapon mod slot per weapon.
- In the campaign, unlock more slots by finding Hard Cases (yellow containers) and completing secondary objectives.
- Hard Cases first appear in Act 2, Chapter 2 — Act 1 has none.
- In Horde Siege, mod slots unlock by levelling up your class.
- Equip your mods at Supply Cache points scattered across each chapter.
- Finding a mod and having a slot for it are two separate things — you need both.
Weapon mods are brand new to the Gears of War campaign in E-Day. For the first time in a mainline Gears game, you can actually customise your guns mid-campaign — swapping barrels, changing ammo types, improving handling, and more. The problem is, when you first pick up a weapon, you have only one slot available. The rest are greyed out and locked.
This guide explains exactly how to unlock more weapon mod slots, where to find Hard Cases, how secondary objectives tie in, and how the system works differently in Horde Siege.
How Weapon Mod Slots Work in Gears of War E-Day
Every weapon in the game starts with a single active mod slot. The other slots are locked and stay that way until you unlock them. This is where a lot of players get confused — you might collect a bunch of mods early on, but not have any extra slots to actually use them in.
There is also an important difference between finding a mod and unlocking a mod slot. Hard Cases and secondary objectives can reward either one — or both. You might walk away from a Hard Case with two new mods but zero new slots, or a slot but no new mod to fill it. Always check what you actually received.
Mods are equipped at Supply Caches, the green equipment boxes found throughout each chapter. These are where you swap weapons, top up ammo, and manage your loadout. Anytime you want to change what mods you have equipped, you need to find one of these caches first.
How to Unlock More Weapon Mod Slots in the Campaign
There are two ways to unlock additional weapon mod slots in the Gears of War E-Day campaign: finding Hard Cases and completing secondary objectives.
Find Hard Cases
Hard Cases are yellow containers scattered across the game’s chapters. They are the main way to unlock new mod slots in the campaign. Each one you open gives you a reward — usually a new mod, a new slot, or both together.
A few things to know about finding them:
- When you are close to a Hard Case, a message appears on the left side of your screen telling you one is nearby.
- Press LB to activate Tac-Com, which will mark the Hard Case on your HUD if you are still in range.
- Hard Cases appear most often in the open-area chapters of Acts 2, 3, and 4.
- Act 1 does not contain any Hard Cases with mod slots — you will not start unlocking extra slots until Act 2.
The first Hard Cases with mod slots appear in Act 2, Chapter 2. That chapter alone contains slots for the Gnasher, Lancer Mk1, Hammerburst, Prototype Lancer, Longshot, Breechshot, Snub, Armor, and Adrenaline Injector. It is one of the most slot-dense chapters in the game, so slow down and explore when you get there.
Complete Secondary Objectives
Secondary objectives are optional side missions that pop up across the open-area chapters in Acts 2, 3, and 4. They are marked with a gold icon on your map once discovered.
Most of the time you find them by walking close to their location and hearing Marcus or one of the Bravo Squad members react to something happening nearby. In Act 4, some secondary objectives are called in over comms rather than discovered on foot.
These missions usually involve holding a position while an NPC escapes or a task is completed — similar in feel to a short Horde encounter. Finishing one rewards you with mods and sometimes extra mod slots. They take roughly 5 to 10 minutes each.
Because they are optional and not marked until you stumble near them, secondary objectives are easy to miss. Stay alert in open-area chapters and do not rush straight to the main objective marker.
Which Hard Cases Give Mod Slots?
Not every Hard Case contains a new mod slot — many just give you a new mod. Below is a breakdown of the confirmed Hard Cases that reward mod slots, based on act and chapter:
Act 2, Chapter 2 – Hold the Line
- General Mod Slot (Gnasher) + Composite Chassis mod
- General Mod Slot (Lancer Mk1) + Close-Quarters Barrel mod
- Armor Mod Slot
- General Mod Slot (Hammerburst) + Huge Magazine mod
- General Mod Slot (Prototype Lancer) + Cover Brace mod
- General Mod Slot (Longshot) + Precision Long Barrel mod
- General Mod Slot (Snub) + Forged Barrel mod
- Mod Slot (Adrenaline Injector)
- General Mod Slot (Breechshot) + Skeleton Frame mod
Act 2, Chapter 5
- Injector Mod Slot
- Disruptor Mod Slot
- General Mod Slot (Gut-Puncher) + Extended Belt mod
Act 3, Chapter 2 – Enemy Lines
- Armor Mod Slot + Hardened Resolve mod
- Pulse Drone Mod Slot
- General Mod Slot (Incinerator) + Cut Magwell mod
Act 3 and Act 4 continue to offer Hard Cases throughout their chapters, many of which include additional mods for the Breechshot, Ripper LMG, Striga, Gnasher, Stim, and more. Keep checking for the on-screen prompt as you explore.
If you want to know more about how Act 1 plays out before the mod system opens up, our Gears of War E-Day Act 1 collectibles guide has you covered for that chapter.
How to Unlock More Mod Slots in Horde Siege
In Horde Siege mode, the system works differently. Weapon mod slots are tied to class progression, not Hard Cases.
Each of the four classes — Assault, Breacher, Marksman, and Medic — has a 30-level progression track. As you level up your class through matches, you unlock new weapons, armor mods, tactical gear mods, and weapon mods along the track. Reaching the required level for a weapon mod makes it available — but does not give it to you for free.
Once a weapon mod is unlocked on the track, you still need to purchase it with Weapon Parts before it can be equipped. Weapon Parts are earned by playing Horde Siege matches and extracting successfully. If your squad fails to extract at the end of a mission, you lose the parts collected during that run.
Weapon configurations in Horde Siege are also shared across classes — if two classes use the same gun, they share the same mod setup for that weapon.
How to Equip Mods Once You Have Them
In the campaign, you equip mods at Supply Cache points found throughout each chapter. These green cases let you refill ammo, switch weapons, and change your mod loadout on the fly. Any weapon you pick up during the campaign — COG or Locust — gets added to your weapon pool at these spots.
You can equip up to the number of slots you have unlocked for each weapon. Mods give things like improved handling, zoom adjustments, changed ammo behavior, and extended magazines. Some are subtle tweaks; others genuinely change how a gun plays.
In Horde Siege, mods are managed in the Classes menu between missions. Weapon mods go under the Loadout tab, while armor and tactical gear mods live under the Gear tab.
For a full breakdown of how the campaign is structured around these systems, check out our Gears of War E-Day chapters and acts explained guide. And if you want to know how E-Day compares to the rest of the series, our biggest changes in E-Day article covers it all.
Tips for Getting the Most Out of Weapon Mods
- Don’t ignore open-area chapters. Most Hard Cases are in Acts 2, 3, and 4 open chapters. Rush the main objective and you will miss the bulk of your slots.
- Use Tac-Com regularly. Press LB whenever you are exploring a new area to check if any Hard Cases are nearby. The game only flags them for a limited proximity window.
- Check what you actually got. After opening a Hard Case, look at your loadout screen to confirm whether you got a slot, a mod, or both.
- Build around your main weapon. If you favour the Lancer or Gnasher, prioritise Hard Cases that unlock slots for those first before worrying about the rest.
- In Horde Siege, extract every mission. Weapon Parts are lost if no one on your squad extracts. Even a tough match is worth pushing through the exit if you have collected parts worth keeping.
Where to Play Gears of War E-Day
Frequently Asked Questions
How many weapon mod slots do you start with in Gears of War E-Day?
You start with one mod slot per weapon. All other slots are locked until you find Hard Cases or complete secondary objectives in the campaign, or level up your class in Horde Siege.
When do you get the first weapon mod slot in E-Day?
The first Hard Cases with mod slots appear in Act 2, Chapter 2. Act 1 does not have any Hard Cases that unlock weapon mod slots, so you will be working with one slot per weapon throughout the opening act.
What are Hard Cases in Gears of War E-Day?
Hard Cases are yellow containers found throughout the game’s chapters, especially in open-area sections. Opening one rewards you with weapon mods, mod slots, or both. A screen prompt and your Tac-Com (LB) can help you locate them when you are nearby.
Do secondary objectives give weapon mod slots?
Yes. Completing secondary objectives can reward weapon mods and mod slots. They appear as optional side missions in open-area chapters across Acts 2, 3, and 4, and are marked with a gold icon on your map once discovered.
How do you equip mods in the Gears of War E-Day campaign?
In the campaign, mods are equipped at Supply Cache points — green equipment cases scattered throughout each chapter. Interact with one to access your loadout, swap weapons, change mods, and refill ammo.
Are weapon mods available in Versus mode in E-Day?
No. Weapon mods are disabled in Versus mode. They are only active in the campaign and Horde Siege, keeping competitive play on equal footing for all players.
