You know what, I recently did this in a copy of Emerald. I wanted an adamant kecleon, never mind why I wanted one. I have nothing in third gen any more because I moved all my good shit, plus I can't even trade.
1) Caught a wild kecleon, checked the crap in my boxes, found a wild zigzagoon with 31 atk. Bred zigzagoon to kecleon until I got a kecleon with 31 attack.
2) Bred 31 attack kecleon to an electrike with 31 speed, received kecleon x2 with 31 attack/speed.
3) Bred 31 attack/speed kecleons until an adamant female popped up, this admittedly took more time, about 2/3 of a box. Also had a fluked 31 spdef in this batch.
4) Bred 31 attack/speed kecleons with 31 spdef, acquire adamant 31 attack/speed/spdef x2. Continue breeding these and manage to fluke a 31 def giving me x/31/31/x/31/31.
Emerald only ever passes three stats, only females pass nature and HP/Def are less likely to pass down. I still got me a 4IV kecleon within a few hours, out of absolutely fucking nothing. It is so much easier in XY it's ridiculous, and people are STILL bitching about it?
>inb4 autist NEET etc