>>54269456>>54269545You can't do gene-splicing on an already developing multicelular organism unless you use viruses and this method is relatively new (which is why they used the COVID-19 "vaccines" to test it). All the gene fuckery had to be done before Mewtwo was even conceived.
When they talk about "horrific experiments" (putting aside the torture of Mew) it refers to multiple failed attempts to create a viable Mewtwo. Those failures resulted in either miscarriages or creatures that died shortly after birth (or Ditto, if you want to believe that).