This system treats guns like **customisable magic weapons** built from interchangeable parts. Instead of finding a new gun every time, players: - Upgrade a **base gun** - Add **mods** that change how it behaves - Make meaningful choices instead of stacking raw damage Think of it like: > **A magic item you build, not one you replace.** #### The Core Idea > **A gun has a limited number of mod slots. > Each mod fills one slot and changes how the weapon works.** You cannot exceed your gun’s slot limit. #### Base Gun Models Before adding mods, you need a **base gun**. | Rarity | Mod Slots | What This Means | Price (gp) | | --------- | --------- | ----------------------------------- | ---------- | | Common | 1 | Simple weapon with a single upgrade | 200 | | Uncommon | 2 | Flexible, early customisation | 750 | | Rare | 3 | Strong, specialised builds | 1,500 | | Very Rare | 4 | High-end, multi-role weapon | 4,000 | | Legendary | 5+ | Signature, story-defining weapon | 10,000 | Note: **Mods are balanced around slot limits**, not just gold cost. | Mod Type | Mod Name | Effect | Price (gp) | | -------- | --------------------------- | ----------------------------------------------------------------------------------------------- | ---------- | | Barrel | Longbite Barrel | +100 ft range, +1 to long range attacks, -2 to hit within 20 ft | 400 | | | Stormcoil Barrel | Lightning damage, crit arcs to nearby target (Dex save) | 800 | | | Hexfire Coil Barrel | Fire damage, crit ignites (1d6 fire/turn, Dex save ends) | 750 | | | Scattershock Muzzle | 15 ft cone attack (Dex save for half) | 500 | | | Astral Piercer Barrel | Ignores cover, crit banishes target (Cha save) | 1,200 | | | Blunderbore Muzzle | 15 ft cone burst, half damage to all targets, 5ft pushback | 300 | | | Frostbite Barrel | Cold damage, hit reduces speed by 10 ft (1 turn) | 700 | | | Silencer Coil | Attacks don’t reveal position on hit | 600 | | | Phasewave Muzzle | Push target 10 ft on hit (Str save) | 500 | | Frame | Repeater Frame | Fire twice per action, second hit can’t Sneak Attack Flat damage(no mod) | 700 | | | Mortis Core Receiver | 2d12 necrotic, regain 5 HP on kill | 1,200 | | | Stormrider Frame | Line lightning shot (30 ft, Dex save), 1/short rest | 950 | | | Heavybolter Assembly | 2d10 damage, bracing gives advantage, -10 ft movement | 700 | | | Sniper Frame | 2d12 damage, +1d10 at long range | 600 | | | Overclock Frame | +1 damage die, weapon jams on nat 1 | 650 | | | Sentinel Frame | Opportunity attacks with gun in melee | 800 | | | Arc Capacitor Core | Next hit after reload deals +1d10 | 750 | | Stock | Gyroscopic Stabiliser Stock | Reroll one damage die, advantage while prone | 400 | | | Witchwood Handgrip | On hit, cast Hunter's Mark (no concentration) only applies to this weapons damage dice | 800 | | | Clockwork Folding Stock | Advantage on Sleight of Hand to hide weapon<br>surprise attacks deal +1d6 once per combat | 250 | | | Tinker’s Counterweight Grip | Ignore melee range disadvantage, +2 to resist disarm | 300 | | Magazine | Alkahest Core | Acid damage, lowers AC by 1 (max -3) on hit | 900 | | | Elemental Glyph Chamber | 1d4: Fire, Ice, Lightning, or Thunder bonus effect | 850 | | | Void Echo Feeder | Roll 2 attacks, use highest | 1,500 | | | Hellsteel Drum | ignore fire resist, 1d8 burn on nat 1 | 650 | | | Shattercharge Feed | Crit forces Con save or stunned (1 turn, 1/long rest) | 1,100 | | | Bloodstone Magazine | Gain temp HP equal to damage dealt (1/turn) | 900 | | | Nullfield Core | Suppresses magical effects on hit (1 round, 1/short rest) | 1,200 | | Scope | Tactical Lens Array | +5 passive Perception, advantage on Initiative, Add advantage on Perception checks while aiming | 400 | | | Voidglass Scope | See invis/ethereal 60 ft | 1,200 | | | Snipeglass Prism | Advantage if stationary on turn | 700 | | Rune | Runestone of Echoes | Miss rebounds half damage to nearby creature | 1,000 | | | Sigil of Time Dilation | Surprise shot before initiative, 1/long rest | 1,800 | | | Phantom Round Circuitry | Shoot through walls (up to 1 ft thick), can’t crit | 1,400 | | | Cursebrand Etching | Target loses Opportunity Attacks for 1 min, 1/long rest | 1,800 | | | Rune of Returning | Teleport gun to hand, 1/short rest | 800 | | Utility | Bayonet Spike | Bonus action melee stab (1d6) | 200 | | | Grapnel Launcher | Launch rope to climb/pull, 3 uses per long rest | 700 | | | Quick-Release Sling | Draw/stow weapon as free action | 300 | | | Smoke Discharge Valve | 10 ft smoke cloud, heavily obscured, 1/long rest | 600 | | | Flashburst Chamber | 15 ft blind burst (Con save DC 13), 1/short rest | 450 | | | Auto-Brace Bipod | Set up to gain +2 AC vs ranged | 400 | | | Shock Net Launcher | Restrain target (Dex save), 1/short rest | 650 | | | Flare Beacon | Illuminate area, reveal invisible enemies, 1/long rest | 350 | #### Balance & Stacking Rules ##### 1️. Slot Limits - Each mod uses **one slot** - You cannot install duplicate mods - Conflicting mods are resolved by the DM ##### 2️. Attack Economy > **No more than one mod may grant additional attacks.** - Mods that grant extra attacks do not stack - A weapon can never exceed normal action economy ##### 3️. Critical Hit Limits > **Critical-triggered effects only trigger once per turn.** - If multiple mods trigger on a crit, the wielder chooses **one** - Prevents crit-fishing abuse ##### 4️. Control Lockout > **A target can only suffer one movement- or reaction-denying effect per round from mods.** This includes: - Speed reduction - Restrain - Reaction denial - Forced immobilisation ##### 5️. AoE Restrictions > **A weapon may only have one cone, line, or area-of-effect mod installed.** Prevents crowd-clearing builds from eclipsing spellcasters. ##### 6️. Repeater Limitation If a weapon fires more than once per action: - The **second hit cannot trigger runes or magazine effects** - Flat damage only unless stated otherwise