I looked on Smogon, they have everything ;-;
It was something like 252 HP/XXX Def/XX Sp.Def, had 0 offensive EVs.
Also, today is my first day of school. I'm really hyped but my activity will obviously go down. Good luck to Black Ice!
Amoonguss is purely a defensive Pokémon. While Leftovers is usually an inferior item in doubles, I think Amoonguss is bulky enough to use it. Or rather, use Black Sludge.