Pokécharms

I had the same question for a Demon Type

Basically, same restrictions as anything else fanmade applies - if it's not your thread, ask the thread creator if they're okay with it. If it IS your thread, be sure to have a proper explanation of type advantages and disadvantages, strengths and weaknesses of these types somewhere where other RPers can see it.

ah okay

Keep your creations balanced, and there shouldn't be much of a problem. Hell, my fanmade region has a fanmade type as well and it's been around since gen 2. XD

What would a Demon type have for weakness besides Fairy and Psychic (and I'd think Ghost and Dark would do nothing to it)

To be perfectly fair, the existing Dark type already IS practically a Demon type! In Japanese, the Dark type is the "Evil" type, and the moves and Pokemon associated with it already demonstrate unfair fighting, manipulation, torture and what have you. Hell, there is a LITERAL HELLHOUND. There's no need to paint that particular lily any further, if you ask me. XD

aw I thought it be awesome to have...never mind then

Well, here is an example of a match up I came up for defense... (I could not put more down because of the character limit...)

Psychic vs Cyber- Technology does what one tells it to do, not what one really wants it to do. They are usually influenced by commands of code, as the mind is almost no use against it. (Resistance)

For the purposes of introducing a type it is sufficient to present a bare-bones version of what the type can do, such as (I'll use my own Crystal-type as an example):