THE DONNIE BEFORE “THE SMART ONE” BECAME A JOB TITLE
Early Mirage gives Donatello interests rather than a résumé. He understands machines, thinks before he acts and is often willing to engage with ideas his brothers would rather punch, but he still participates fully in the violence and improvisation of the original comic.
That distinction matters. Later adaptations often need each Turtle to communicate his function within seconds. Mirage had more room for overlap. Donnie could be the mechanically minded brother without every machine, alien device or plot complication existing solely for him to explain.