It is not the only Pokemon with this exact typing anymore
No because gastly shares it’s type
Zapdos?
Gyarados
no. another hint: has one or more similarities (1 i came up with mysef) to tangela, but is not from generation 1.
Ferroseed/Ferrothorn?
No. Not the grass typing.
Piloswine?
No, because both Swinub and piloswine were introduced in the same generation of pokemon
The last few I know with a simularity don’t have a unique typing at all.
Similar to tangela: the only Pokemon with its single type in its debut generation.
Coincidentally, the yet to be named Pokemon his typing already existed before the generation that brought the pokemon
So… The type combo was there but its the first one anyway? How?
I have an idea how, but need to look for the right fitment with the other conditions.
EDIT: Carvanha?
No. Hint: it’s gen 3
Blaziken?
No.
One other guess before I give the last hint.
Mawile?
No. Last hint: it has but 1 type
Absol??