Hydras: WoW Battle Pets

Drop: Hellscream Laborer [35], Kor'kron Marauder [35], Mercenary Engineer [35]

Zone: Northern Barrens

Approximate Drop Rate: 1 in 6,600

Drop: Varasha's Egg

Zone: Spires of Arak [30-40]

Drop Rate: 1 in 1

Drop: High Warlord Naj'entus [??+]

Zone: Black Temple

Approximate Drop Rate: 1 in 20

Drop: Scale Matriarchs [50]

Zone: Nazjatar

Approximate Drop Rate: Unknown