Crafting skill.

Guns

Rank 1

Blunderbuss: At-will, cone 3; heavy/medium/light piercing damage (depending on distance). Fires 5 sling bullets at a time.
Steam Pistol: At-will, ranged; medium piercing damage. Requires ammunition (sling bullets).
Stun Baton: At-will, melee; target is stunned for 1 round (Con reduces to half movement and disadvantage to attacks). Lightning resistance/immunity applies.

Rocket Launcher: At-will (reload move), ranged, burst 2; medium explosive damage.
Sniper Rifle: At-will, ranged; heavy piercing damage, fires special ammunition, reload is a bonus action. As a move action, you can use the scope, rendering you effectively blind to your surroundings, but granting advantage to ranged attacks, and the ability to fire at extreme range.

Etherlance: A weapon capable of phasing through matter and striking etheral targets.
- At-will, std, melee; as normal melee weapon, but phases through armor and can pass through thin walls (1 inch of stone, 3 inches of wood)
- sniper ability tbd
Railgun: At-will, line 50/1; inflicts heavy kinetic damage (siege capable), ignores armor and resistance.

Aimbot 3000: At-will, bonus; you gain advantage to your next ranged attack against a chosen target, provided neither of you moves more than 30 feet before you take the shot.
Goblin Glider: Recharge (short rest), reaction; while falling, you can deploy this glider to slow your falling rate to 60 ft per round (causing no damage when you hit the ground), and (optionally), each round you fall, you can move horizontally up to 5 ft per vertical foot fallen. Can be detached as a bonus action; otherwise, until detached or reset, the glider causes disadvantage to any maneuver requiring you to fit through a tight space.
Grappling Hook
Transmogrifier Ray: Recharge 33%, ranged; target becomes a useless animal (Con ends, damage ends).
Web Launcher: Recharge 33%, ranged; subject is caught in an electrified web of metal cables. Subject can attempt escape using Dex or Str vs your DC. If they fail, they are immobilized.
Universal Translator: Constant; this headgear combines an earpiece, a mouthpiece, and a lens, granting the ability to understand any non-archaic form of verbal or written language you perceive, and translating your own spoken language into the same via a croaking, mechanical voice. Grants advantage to Linguistics checks to interpret archaic or magical languages.

Carbonite Blaster: At-will, std, range 3, energy 3; subject must pass a Con save or be immobilized and invulnerable (on save, they are chilled). If nothing else happens, they are free after 3 rounds. However, if you use the blaster on them again, they must pass a Con save or be permanently petrified. The effect is reversible by anyone other than the subject.
Electrified Web Launcher: Your Web Launcher now inflicts heavy lightning damage each time they attempt a save to escape. They must pass a Con save when shocked or be stunned for 1 round.
Etherscope: Constant; you can see into the ethereal plane, granting the ability to see ethereal, incorporeal, and invisible creatures (though not necessarily the ability to interact with them). You can also see magical energy, detecting the spellcasting type and max level of all creatures in your line of sight.
Threat Analyzer: At-will, bonus, ranged; you can analyze a single target, determining its level, type, current HP, movement, and AC. By passing an Artifice skill check, DC 10 + CR, you can also determine its damage resistances and immunities, and any damage vulnerabilities.

Chronoscope: Constant; you see and hear a few seconds into the future, making it kind of difficult to walk or hold a conversation, but granting advantage to Initiative rolls, and enabling you to convert any bonus, free, or move action into a reaction once per round. (this is OP)