>>713701623
>what does it add to the design?
Im gonna preface this post by saying type identity has fucking disintegrated as this series went on and only Bug really retained some semblance of it.
Normal is the everyman type, like non-elemental monsters in every other game (you wouldnt give a special element to a regular ogre for example), but Pokemon decided to subvert the usual "unaspected" type and make it have properties. It's primarily given to creatures that dont match up with any of the other types (especially in gen 1 where the types where more like categories rather than mix and match elemental powers). A rat, a housecat, fat pink blobs, a bull, a fat bear. It's given to regular birds because they have to land sometime, and it's also given to pokemon who change type as their main gimmick. Porygon is data come to life, it can change its type at will with Conversion, Ditto can turn into any Pokemon, etc. Now when they started mixing it with other types, it was usually because the creature still had some "plain" aspect about it. Girafarig is half normal giraffe, bibarel lives in water but it's still just a big rodent, Sawsbuck only has leaves on its antlers and it can lose them.
Like I said though, type identities nowadays are in fucking shambles. Psychic probably covers more random bullshit than Normal does, fucking Pokemon Clover has more logic behind its use of Fairy type, like 10+ robots got added and only 2 of them are Steel type, and we STILL don't have a Rock/Ghost despite there being
>a malevolent spirit pokemon bound to a stone
>a sarcophagus pokemon
>an undead coral reef pokemon (it's a regional form, the OG is water/rock)
>a regional form of the sarcophagus pokemon based on runestones
