Once you reach SNO (Small Nachtnebel Ordinal), you can still increase the depth with a number. SMO_n DOES increase the cardinality, but:

SNO[1]_0 = SMO_0

SNO[2]_0 = depth increase of SMO_0, exactly like Suttner or Baus.

LNO (Large Nachtnebel Ordinal) can do the same. Inaccessible Nachtnebel Ordinals cannot do this because they would just be themselves no matter how many times you raise their depth.