>>33463933If you breed something with Ditto, your options for egg moves and passed on TM moves are lesser in comparison to if you bred with a natural egg group member. Also females used to be the only one to pass down its ability, although this isn't true anymore, though female parents still have a greater chance of passing it down then males. Back in gen 2, a pairing with Ditto would inherit the ditto's IV's instead of the natural parent. This ensures that good starter pokemon are hard to find, even if its trivial