We have been fighting over this more than a week. I want to see who is right. (I do not have either Ruby or Sapphire.)
Haha no, your friend is lying
The only known forms of Deoxys are Attack, Defense, and Speed
There are Speed Deoxys, Attack Deoxys, and Defense Deoxys (and of course the normal Deoxys). But there isn't any Deoxys with an accuracy form.
Hope I helped!