Nominals ending with ⟨-ton⟩/⟨-tön⟩: those with the derivational suffix -ton (roughly "-less") and negative participles (-maton). Inverse quantitative consonant gradation.
The inflectional stem is formed by replacing the final ⟨-n⟩ with ⟨-ma-⟩/⟨-mä-⟩, and strengthening the preceding ⟨-t-⟩ (unless it comes directly after a consonant). The final ⟨-a-⟩/⟨-ä-⟩ is dropped before the plural marker ⟨-i-⟩.
Partitive singular ending ⟨-ta⟩/⟨-tä⟩, partitive plural ending ⟨-a⟩/⟨-ä⟩, and standard genitive plural ending ⟨-en⟩. The genitive plural with ⟨-nten⟩ is rare/archaic/dialectal.