Homebrewing a Reseach/Science skill

[Tyrex]

The general idea is that the skill is used to make things like engines, guns, or other things like them inside of a semi magical world (magic is heard of, but rarely seen or used except for major cities). I have ideas, but I sometimes over complicate things or make them to strong.

The original idea is a skill that would allow a player to research and make an item that either mimics a spell or effect. For example, he may make a gun that fires a single magic missile per round or a flamethrower for burning hands.

It is unaffected by magic immunity or anti-magic effects, but it also means it would not be effected by metamagic or caster level. It would never get better in other words. Worse then the real deal, but it can be used once a round, every round with no problems by a none wizard or sorcerer.

It would also not be able to make some things just because they can't be converted (true strike).

Would it need a feat to be used, similar to craft wondrous item? What kind of class would have it as a class skill? Is this something that should be used, or am I just making something that is game breaking?

[Ellrin]

The general idea is that the skill is used to make things like engines, guns, or other things like them inside of a semi magical world (magic is heard of, but rarely seen or used except for major cities). I have ideas, but I sometimes over complicate things or make them to strong.

The original idea is a skill that would allow a player to research and make an item that either mimics a spell or effect. For example, he may make a gun that fires a single magic missile per round or a flamethrower for burning hands.

It is unaffected by magic immunity or anti-magic effects, but it also means it would not be effected by metamagic or caster level. It would never get better in other words. Worse then the real deal, but it can be used once a round, every round with no problems by a none wizard or sorcerer.

It would also not be able to make some things just because they can't be converted (true strike).

Would it need a feat to be used, similar to craft wondrous item? What kind of class would have it as a class skill? Is this something that should be used, or am I just making something that is game breaking?

These sound pretty weak, to be honest, due to the blasting focus and low level. You could probably just make a skill akin to Craft (alchemy), and maybe give some class-based bonuses or abilities depending on what sort of people should be more adept with these inventions. You could think about some feats that might boost "CL" on the effects a little.

A person decked out with inventions like your examples would probably be pretty good at very low levels (especially without any primary casters in the party to outshine them), but without any scaling, they'll be kind of lagging behind if they try to focus on them, even if you take all spells, SLAs, and (Su) abilities out compared to a pouncing barbarian or especially to a ToB class. Now if you include some items that mimic battlefield control spells (like grease), they'll have a few more levels of utility even if they really focus on crafting and using these items; even then, by mid-levels, if we stick with the level of effects you're giving as examples, we're talking about items people will be using maybe once a combat.

You could potentially increase scalability by making these useable as iterative attacks--especially if they can be attached to existing weapons/shields/equipment that people would be holding anyway, so they don't have to waste actions switching what they're wielding.

[Tyrex]

These sound pretty weak, to be honest, due to the blasting focus and low level. You could probably just make a skill akin to Craft (alchemy), and maybe give some class-based bonuses or abilities depending on what sort of people should be more adept with these inventions. You could think about some feats that might boost "CL" on the effects a little.

A person decked out with inventions like your examples would probably be pretty good at very low levels (especially without any primary casters in the party to outshine them), but without any scaling, they'll be kind of lagging behind if they try to focus on them, even if you take all spells, SLAs, and (Su) abilities out compared to a pouncing barbarian or especially to a ToB class. Now if you include some items that mimic battlefield control spells (like grease), they'll have a few more levels of utility even if they really focus on crafting and using these items; even then, by mid-levels, if we stick with the level of effects you're giving as examples, we're talking about items people will be using maybe once a combat.

You could potentially increase scalability by making these useable as iterative attacks--especially if they can be attached to existing weapons/shields/equipment that people would be holding anyway, so they don't have to waste actions switching what they're wielding.

Yeah, or I could make the "CL" increase by how high they rolled. If they got 5 or more above the DC for example, then it would go up for every 5 increment. This is meant to work with ANY spell (within reason) too. The higher the Spell level the higher the DC. Things like clone or polymorph would be higher level examples.

This is meant to be more along the lines of a guy buffing his party by giving multiple people the items then just stacking them all on just him. Why have both a glove that mimics shocking grasp and a pair of glasses that work like darkvision (night vision goggles) when you can give them to the fighter and the ranger respectively. They get more millage out of them.