Adds the GS-004-A Jack Shotgun and GS-004-B Hammer Ammo Backpack.

[Mrrpip]

About the PR

From the latest imports of GS, we present... The Jackhammer! 48 rounds of burst fire frenzy! A cool laser sight! Elite 4 gauge action! And.... The speed of a tortoise. Oh dear.

Included in this PR is:

• One shotgun, the 4 gauge Jack. With a 3 round burst, a higher than usual spread at 1.75 times and a 35% damage malus
• One backpack, with a high slowdown and the lack of an internal storage but a 48 shell capacity.
• A canister to hold said 48 shells, fits handily into the backpack.

The shotgun and backpack are research-able alongside the Big Buddy and Ratel.

In a nutshell, did this to have some fun with the EL-HAMMR from Goob's concept, along with trying out the new DamageModifier stat.

Why / Balance

Well, the why is... I may have had a bit of an Planetside 2 NC binge-session and I just love heavy equipment.

As for the balance, figured that the 2 second wield time, high spread, slow movement speed, big sprite and obvious laser sight would all contribute to keeping the TTK in check by making a full OHKO burst very difficult.

Could probably be a bit of a menace in tight ships, though.

Media

**The below image is a bit out of date, went with discord feedback over the spread. Check code.**

2026-04-19.02-20-37.mp4

Requirements

• I have read relevant guidelines/documentation to this PR found on our devwiki.
• I have added media to this PR or it does not require an ingame showcase.
• I can confirm this PR contains either no AI-generated content, or AI-generated content that meets our guidelines.

How to test

• Check research tree
• Check fabs for Gun, backpack, 2 canister types.
• Check that it loads from backpack.
• Rooty tooty point and shooty.

Breaking changes

Changelog

🆑

• add: Local Generic Systems have shipped a new assault cannon: The GS-004 along with it's backpack based ammo system.
• add: Adds recipes to the Advanced Mercenary Weapons node.

[github-actions]

RSI Diff Bot; head commit 8a612d4 merging into 4ea83d3
This PR makes changes to 1 or more RSIs. Here is a summary of all changes:

Resources/Textures/_Mono/Clothing/Back/Backpacks/jack_backpack.rsi

State	Old	New	Status
base			Added
equipped-BACKPACK-mag-0			Added
equipped-BACKPACK			Added
icon			Added
inhand-left			Added
inhand-right			Added
mag-0			Added

Resources/Textures/_Mono/Objects/Weapons/Guns/Ammunition/Magazine/4_gauge/4_gauge_canister.rsi

State	Old	New	Status
base			Added
mag-0			Added
mag-1			Added

Resources/Textures/_Mono/Objects/Weapons/Guns/Shotguns/jack.rsi

State	Old	New	Status
base			Added
bolt-open			Added
icon			Added
mag-0			Added

Resources/Textures/_Mono/Objects/Weapons/Guns/Shotguns/jack_inhands_64x.rsi

State	Old	New	Status
equipped-BACKPACK			Added
equipped-SUITSTORAGE			Added
inhand-left			Added
inhand-right			Added
wielded-inhand-left			Added
wielded-inhand-right			Added

[Mrrpip]

Some issues I've noticed and that I may need help with is related to the magazine sprites.

Namely:

• The backpack always displays as loaded on the character's worn sprite.
• The shotgun's icon is always displayed as loaded too.

[Greenwall-Exe]

this might be worthy of its own node honestly. Theres also a backpack fed laser weapon if you wanna retool it and you could put both of them together as their own research

[Mrrpip]

this might be worthy of its own node honestly. Theres also a backpack fed laser weapon if you wanna retool it and you could put both of them together as their own research

Funnily enough, that is what it was based off of, The EL-20 HAMMR. As for a new node, I'm not certain. Maybe if there were other heavy guns to lump it in with or an armor set or something, but eh....

[NazrinNya]

no need for new node

[Greenwall-Exe]

no need for new node

48 round cap on a 4 gauge even if its got a 35% reduction, thats a lot of rounds. If it were paired up with like weapons i think a new node would be warranted, unfortunately its kind of its own thing at the moment. I could see this as the ballistic option, The HAMMR is already a thing just needs tweaked to be useful, then maybe we add a third pack, maybe a mini tesla repeater shoots tiny teslas that dont taze

[NazrinNya]

no need for new node

48 round cap on a 4 gauge even if its got a 35% reduction, thats a lot of rounds. If it were paired up with like weapons i think a new node would be warranted, unfortunately its kind of its own thing at the moment. I could see this as the ballistic option, The HAMMR is already a thing just needs tweaked to be useful, then maybe we add a third pack, maybe a mini tesla repeater shoots tiny teslas that dont taze

add the HAMMR and whatever that tesla repeater is and we can talk

[Mrrpip]

no need for new node

48 round cap on a 4 gauge even if its got a 35% reduction, thats a lot of rounds. If it were paired up with like weapons i think a new node would be warranted, unfortunately its kind of its own thing at the moment. I could see this as the ballistic option, The HAMMR is already a thing just needs tweaked to be useful, then maybe we add a third pack, maybe a mini tesla repeater shoots tiny teslas that dont taze

add the HAMMR and whatever that tesla repeater is and we can talk

In this PR or are we talking in the context of a different PR?

I should probably set it to draft in the former case.

[NazrinNya]

no need for new node

48 round cap on a 4 gauge even if its got a 35% reduction, thats a lot of rounds. If it were paired up with like weapons i think a new node would be warranted, unfortunately its kind of its own thing at the moment. I could see this as the ballistic option, The HAMMR is already a thing just needs tweaked to be useful, then maybe we add a third pack, maybe a mini tesla repeater shoots tiny teslas that dont taze

add the HAMMR and whatever that tesla repeater is and we can talk

In this PR or are we talking in the context of a different PR?

I should probably set it to draft in the former case.

other pr
Your is fine