When the consonant is unvoiced and aspirated, the diacritic shifts its airstream to be ejective. If the language doesn't have ejectives, then it turns into its plain form.
When the consonant is breathy voiced, it becomes implosive. If the language doesn't have implosives, then it turns into its plain form.
When the diacritic is applied, the consonant becomes prenasalized. This is distinct from the bilabial nasal /m/ that appears on its own, as this one occurs with other consonant graphemes. In this case, no additional lines need be added to the ingungu, as the place of articulation is given by them instead.
When its used on an ejective click consonant, the ingungu symbolizes prenasalization. If it's a plain click, then the click becomes a nasal one.
