Old School Runescape continues to be one of the most played MMORPG's around, despite being based on a game that came out in 2007. Whilst players dedicate countless hours of their precious time developing skills, playing minigames, or defeating bosses they sometimes can happen upon an absurdly rare item, a pet.

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Pet's are a mini version of bosses or skill-affiliated animals that will follow you around as a new tiny companion on your journey throughout Gielinor. Although no pet is essentially easy to obtain (not counting the faithful pet rock) there are some companions that are especially rare for your character to stumble across.

10 Skilling Pets

OSRS Skilling Pets Racoon, Golems and Heron

There are 8 Skilling Pets in Old School Runescape, with each one giving you around a 30% chance of obtaining it from levelling a skill from 1-99.

Although you of course always have the rare chance of stumbling across one with all the skill grinding you have to do, a 30% chance for that much work is nothing short of exhaustive. It is true that most players looking to max their skills may encounter at least one on their account's journey, but just don't be expecting to see a lot of them.

9 Golden Chinchompa - Hunter Skilling Pet

Golden Chinchompa Pet OSRS

If getting a specific skilling pet wasn't enough, imagine then having to roll for a special color.

Chinchompa's come in three colors: grey, red and black. If you find yourself rewarded by the appearance of this skilling pet whilst trapping its brethren in boxes, the game allows you to choose the color you'd like your new furry companion to be. While right-clicking it to change this you have the 1/10,000 chance of it turning into a glorious golden Chinchompa, quickly becoming the envy of all.

8 Vet'ion Jr. - Vet'ion

Vetion OSRS

Vet'ion is considered by many to be one of the hardest bosses in the Wilderness, but luckily he has a safe spot making him slightly easier for players with high combat and the right know-how to take him down.

Still, defeating Vet'ion is no laughing matter, and even with the safe spot, he can take around 5 minutes a kill. His valuable Dragon Pickaxe and Ring of the Gods drops also make his pursuers a prime candidate for Pk'ers prowling the area, making his 1/2000 pet drop not as great as it seems.

7 Callisto Cub - Callisto

Calisto Cub Pet Osrs

At a 1/2000 chance this tiny bear cub doesn't appear to be the hardest pet to obtain, but that just means you've never faced its furry parent.

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Callisto can only be killed around 10 times an hour taking a lot of time to bring down, and that's ignoring the fact that its habitat is a popular killing spot for PK'ers looking to cash in on the Dragon Pickaxe drops players can obtain from this fearsome beast.

6 Lil' Zik - Theatre Of Blood

Lil'Zik Osrs

One of the newer pets, Lil' Zik is the much smaller version of the Theatre of Blood's head vampire Verzik Vitur; currently the hardest monster in Old School Runescape.

Upon completion of the Theatre of Blood, depending on your performance within the Raid and your team you can have between a 1/650 or 1/6'500 chance of obtaining Lil' Zik. Although 1/650 doesn't seem too bad, just factor in how long one of these raids takes along with how you consistently have to be top of your team to quickly realize getting this monstrous spider is no mean feat.

5 God Wars Pets

God Wars Pets Osrs

The God Wars bosses are no joke, being some of the hardest content back in the old days and still continuing to give those same players grief all these years later.

All the pets are a 1/5000, not coupled with how hard they all are - especially Kree-arra and K'ril Tsutsaroth who are some of the rarest obtained pets in the game. Don't discount the fact that each time you leave and then want entry back into the boss's lair it also requires either an Ecumenical key from the Wilderness God War's Dungeon or for you to kill 40 followers of each domain. Yikes.

4 Corporeal Critter/Pet Dark Core - Corporeal Beast

Coporeal Beast OSRS

A pet rarely seen in game, the Corporeal Critter (or Pet Dark Core if you choose to metamorphize) comes in at a 1/5000 chance, and that's not even acknowledging that this beast is considered by many the hardest boss in Old School Runescape.

To kill him it's recommended to bring a team of up to five people, as with too many he can even start healing himself. Even with a group of five this boss takes a long time to bring down, and because of this it still today drops some of the most expensive items in the game including the Elysian Sigil which can reach up to 1,000,000,000 gold on the Grand Exchange.

3 Jal-Nib-Rek/TzRek-Zuk - TzKal-Zuk

Jal-Nib-Rek OSRS

Jal-Nib-Rek (or if you wish to metamorphize, TzRek-Zuk) is the pet drop from completing the Inferno and defeating its main boss TzKal-Zuk.

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The Inferno is no laughing matter being by far some of the hardest Old School Runescape content around, with people devoting hours to its completion to be awarded with the Inferno Cape. The only reason Jal-Nib-Rek doesn't feature any higher is its 1/100 (or 1/75 on a slayer task) chance of dropping on an Inferno's completion, along with being able to trade in that beautiful Inferno Cape for another 1/100 chance.

2 Bloodhound - Master Clue Scroll Casket

Bloodhound Pet Osrs

By far a rare pet to ever see in the game let alone even think about owning yourself is Watson's trusty Bloodhound.

Getting one of these adorable pups is no mean feat, with a drop rate of 1/1000 from a Master Clue casket. Master clues are some of the hardest content in the game, requiring the completion of major quests, high skilling requirements, and expensive and hard-to-find items in order to complete their many steps. This pup is truly Runescape's goodest and rarest boy.

1 Pet Penance Queen - Barbarian Assault

Penance Queen OSRS

A pet seldom seen, and with good reason. The Pet Penance Queen is the ultimate brag in Old School Runescape.

The Pet Penance Queen is only obtainable by going for a high-stakes gamble in Barbarian Assault. A high-stakes gamble requires a 500 honor points bet and needs you and your team to successfully complete every wave and kill the Penance Queen at the end in order to qualify for a reward.

A full Barbarian Assault game can already take around 30 mins, and after betting high stakes and being successful, it's still only a 1/1000 chance you're walking away with a bonafide queen.

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