Death and Decay

Vendor: Nigel Rifthold

Zone: Drustvar

Cost: 100 (unlimited supply)

Vendor: Olly (H)

Zone: Dazar'alor

Cost: 100 (unlimited supply)

Requires: A Shady Message

Quest: Critters of Draenor [1]

Zone: Lunarfall, Frostwall

Drop: Traveler's Pet Supplies

Approximate Drop Rate: 1 in 25

Pet Battle: [25] The Maw

Drop: Fallen Adventurer's Cache

Zone: The Maw

Approximate Drop Rate: Unknown

Vendor: Trading Post

Zone: Orgrimmar (H), Stormwind (A)

Cost: 650 (unlimited supply)

Drop: The Lich King [??+]

Zone: Icecrown Citadel

Approximate Drop Rate: Unknown

Profession: Archaeology - Fossil

Artifact: [Fossilized Hatchling]

Drop: Sha of Pride [??+]

Zone: Siege of Orgrimmar (LFR or Flexible)

Approximate Drop Rate: Unknown

Pet Battle: [3-6] Silverpine Forest; [3-6] Bloodmyst Isle; [6-7] Hillsbrad Foothills; [12-13] Eastern Plaguelands

Trading Card Game: Worldbreaker

Vendor: Micro Zoox

Zone: Dun Morogh

Cost: 2 (unlimited supply)

Pet Store 

World Event: Day of the Dead

Quest: The Grateful Dead [1]

Achievement: How to Keep a Mummy

Category: Battle Dungeon

Achievement: Pet Battle Challenge: Stratholme

Category: Pet Battles

Drop: Blindlight [50]

Zone: Nazjatar

Approximate Drop Rate: Unknown

Drop: Nest Egg

Zone: Azj-Kahet

Drop Rate: 1 in 1

Pet Battle: [17-18] Deadwind Pass

Time: Early Morning

Pet Battle: [25] Nazmir

Pet Battle: [22-23] Icecrown

Drop: Curious Wyrmtongue Cache

Zone: Broken Shore [45]

Approximate Drop Rate: Unknown

Zone: Torghast

Approximate Drop Rate: Unknown

Vendor: World Vendors

Cost: 50 (unlimited supply)