[MichalSternik]

For curious, about the actual usage of `potrzebie` in polish:

potrzeba is a neutral form of a noun, meaning `a need.

`potrzebie` is a inflected form, dativus i guess.

example of usage: `trzeba pomagać ludziom w potrzebie' ~> `one needs to help people in need`

[eafkuor]

Wouldn't your usage be miejscownik/locative?

[uryga]

it is.

[w kim?/w czym? w potrzebie] is locutive.

[komu?/czemu? tej potrzebie] would be dative.