D.Shaffer said:
It might just be me being argumentive, but I have a hard time seeing a guy who uses lots of alchemical devices as being 'Martial', powered. He isnt relying on his skill so much as exploiting the effects of his gear. It'd be like claiming Artemis was a martial controller because he used the effects of his sword.
It takes skill to use his equipment. For instance, it isn't enough to have the know-how to make alchemical grenades. You also gotta have a good throwing arm, too, if you want to put those grenades to good use. The guy doesn't just make items. He uses them to fight. And to put them to the most use, he'd have to have some kind of combat training. Possibly somewhere inbetween a Warlord and a Rogue.
Martial doesn't just describe people with strong sword arms, though. The Rogue, for instance, is a Martial character who focuses on doing things with skills that other classes can't. The Warlord does the same with his leadership and inspirational abilities. In the Artificer's case, he'd be taking his natural craftiness and inventiveness to a higher level then most. As the article on power sources said...
The martial power source is about taking resources and abilities that have clear limits for other classes and demolishing those limits through focus, training, and skill.
Anyone can work up a way how to make a firearm, but an Artificer type would be able to sharpen his natural inventiveness to such a degree that he can build a firearm which fires explosive acidic grenades at the enemy. He gains this ability through focus, training, and skill.
As for how to keep their equipment mostly in their hands, one could simply limit it through the use of Feats as well as similar rules like poisoning. You can use alchemical explosives, but there's a chance it might explode in your hands unless you're an Alchemist who's properly trained in the care and use of such equipment. You can use a Blunderbuss if you like, but you'll have to burn a Feat to gain proficiency in it, as it's a rare piece of equipment that one wouldn't normally be able to train in. Hell, one could give such a Feat a prerequisite, saying that you have to be an Alchemist to take in. In which case, anyone who isn't an Alchemist would always suffer a -4 to hit with such a weapon. It's just to complex a device to properly operate unless you're a trained Alchemist. Or say that such a device needs to be regularly maintained by an Alchemist, and if not, then it eventually malfunctions or stops working altogether. We are talking about pieces of equipment that are fairly unusual and complex in comparison to what most medieval types are used to. It wouldn't take a whole lot to come up with reasons why those items tend to stay in the hands of Alchemists.