I'm going to skip doing anything about nouns right now, because I suspect Thuthic, like Tocharian, is going to drop a bunch of peripheral cases and then reinvent a whole bunch of new ones. Instead we'll look at the verbs.

Verbs distinguish past from present from future, perfective from imperfective (only in past tense), and indicative from "subjunctive" (really optative) mood. Originally this was along a Greco-Aryan line, but the system has become much more transparent under the influence of the surrounding Uralic languages.

The basic template is:

(augment)-stem-(perfective /s/)-thematic vowel-personal endings.

An active and a mediopassive exist. Endings:

Primary Active
-m    -mas
-š    -θä
-s    -:s

Secondary Active
-n    -mas
-s    -θä
-Ø    -n

Primary Mediopassive
-me    -meta
-se    -tä
-θe    -:θe

Secondary Mediopassive
-ma    -meta
-sa    -tä
-θa    -:θa

(A colon before an ending indicates that there was often a lengthening in the thematic vowel.)

(just realized I have a lot more shit to get done today than I thought I did, so I've got to go.)