How would this work in the world of D&D mechanics? (Also PF)

[Kavenoff]

Heya GitP! Last time I posted was asking about a half-elf with an intelligent item as a grafted arm (made from a templated dragon turtle). I would have said thank you, but my browser was having issues with posting, and then I lost login info until a day ago. Anyways... thanks for your help on that! On to my next question.

I'm trying to figure out how the Charge Blade (a weapon from the recently-released Monster Hunter 4 Ultimate) would work in the 3.x/Pathfinder rulesets.

Here's a good example of a couple of videos to explain it WAY better than I can myself.

https://youtu.be/icrj8FmvIp4?t=3m (earlier in the video is the Insect Glaive/Kinsect, a different weapon)
https://youtu.be/J1LE1D5YSZM (there's bound to be ads on this guy's videos)
https://youtu.be/gPc90az3HC0
https://youtu.be/c16jJZUbyd4

Those are the original gameplay video for the charge blade (it can give enemies concussions (knockout) in certain axe mode attacks) and the mechanics explained.

The number one thing that I want to figure out is how filling and releasing the phials works mechanically, as well as explained via simple physics (friction causing heat causing blood to fill them? *shrugs*)

Thanks! You guys are awesome!

[GilesTheCleric]

Without knowing more about the franchise's aesthetic, I'm not entirely sure what's going on. In the first video, is the sword causing explosions, or do all weapons make particle effects like that on hit? Additionally, did the sword merge with the shield to become an axe, or was it just the sword?

For weapon transformations, look at the Morphing weapon enchantment (Und 69). For adding poisons or other alchemical substances to weapons via phials, look at Weapon Capsules (CAd 121). Other types of things like simply using (mental) commands to de/activate enchantments on a weapon could also be fluffed to be phials; weapon crystals like the witchlight reservoir (MIC 66) might also do what you want.

For stunning weapons, look at the Stunning/Surge (MIC 44), Brutal Surge (MIC 30), Paralyzing (MIC 39), or Clouting (CAr 143) enchantments.

[Kavenoff]

To answer both major questions: the sword combines with the shield for axe mode, and the axe does explode (but only with loaded phials).

Thank you so much for your help so far, by the way. I forgot to mention that the Monster Hunter series has no magic, and the closest they come is basically elemental (fire, ice, water, thunder, dragon) alchemically-enhanced weapons.

[GilesTheCleric]

Ah, I see; thank you for clarifying.

If you want weapons that come together or separate, I think there's rules in CS for multi-part weapons, but those are single weapons. There might have also been a rule for separable double weapons; with a lenient DM, I don't see why you couldn't have a double weapon with ends of different types (eg. sword+axe). I seem to recall a multi-headed weapon in the AaEG (perhaps it was a rod?).

Most effects in dnd are magic-based, unfortunately. You can always still fluff them as being mundane. If you want to get complex with SLAs (spell-like abilities) or SU (supernatural) abilities, then those technically aren't magic; there might be some monsters with abilities you'd like, but before delving into that you should have a very specific idea of what you're after, since a build including that method will probably be complex if it's not magic-dependent.

Your best bet for mundane abilities is the Tome of Battle. Some of the maneuvers within are probably similar to what you could do in a 3rd person action game, such as rolls, jumps, short teleports, attacks with two weapons at once, charges, etc.

[Solaris]

There are alchemical blades in one of the Eberron books, and Complete Adventurer (if I recall correctly) has stuff for alchemical weapon capsules. In D&D, however, such effects are best represented (without homebrew) through magic.

[Kavenoff]

I don't know if it was shown, but in the "guard point" video, there was a little red shield symbol under the stamina (yellow) bar. That is basically a "better guard" mode that also automatically releases all loaded phials at once with the super hit (the one that makes it go back to sword-and-board mode), which can be done from not attacking at all. The better guard mode stagnates after a little while (~1 min), and disappears completely after another 3o seconds, but neither loaded nor unloaded phials do.

Gonna probably make the better guard mode "stagnating" thing happen.

Thanks again for your help, folks.