Lanticore Spawnling
Source: Drop. No one knows what deep part of Blackwing Descent the Lanticore was kept in, but it probably smelled pretty awful. Dragonkin type. The drops from which is a rare elite in the revamped in WoD. will not appear in every instance of running the dungeon but I assume when he does appear, he will have a 100% drop rate on the pet.
The 
Lanticore Spawnling is a battle pet that drops from The Lanticore, a rare elite found in Upper Blackrock Spire Heroic mode.
Guide awaiting review
Enter UBRS Heroic Mode
Set the dungeon to Heroic difficulty before entering Upper Blackrock Spire. The Lanticore only appears in Heroic mode, so normal difficulty runs will never yield this pet.
Search Kyrak's Room
Head to Kyrak's room — the old Rookery area — and check whether The Lanticore has spawned. The Lanticore does not appear in every instance; its spawn chance is roughly 5%, so most runs will find the room empty.
Defeat The Lanticore
If The Lanticore is present, defeat it and loot the corpse. Under personal loot, the pet has approximately a 20% drop chance, so a sparkly corpse does not guarantee the Lanticore Spawnling will appear in your loot.
Reset and Repeat
You can run up to 12 lockouts per day by resetting the instance. Community farming data suggests roughly 150 total attempts were needed before the pet dropped, with The Lanticore appearing only 7 times across those runs.
Tips
The Lanticore Spawnling is available on the Auction House if you prefer to skip the farming process.
