Silkbead Snail or any other snail. This amazing pet rocks against most non-flying opponents. Shell Shield early to avoid little Dots like Swarm , Acidic Goo , Immolate . Then Dive : if you can do that just before your opponent strongest ability. From now on, Absorb until Shell Shield is about to fa...
Been lucky as hell to having collected one Flawless Battle-Stone in a random encounter while leveling my pet to 25... and already used it before having a clue to its rarity!
Sigh, i hope my luck will go on... i have so many pets to upgrade...