Are there? If so, I haven’t heard of them — I thought that consonant clusters were formed by regularly adding the conjunct form of the second consonant below th

Are there? If so, I haven’t heard of them — I thought that consonant clusters were formed by regularly adding the conjunct form of the second consonant below the first consonant. (I do know that Devanāgarī and closely-related scripts represent clusters using irregular ligatures of consonants, but I don’t believe this method is used in Javanese.)