12 Hardest Bosses in Old School RuneScape (Ranked)This post may contain affiliate links. If you buy something we may get a small commission at no extra cost to you. (Learn more).
Every adventurer in Old School Runescape is looking for the next big challenge.
And there’s no bigger challenge than facing some of the most punishing bosses in all of Gielinor!
Defeating these bosses is the key to unlocking the best gear in the entire game. And you can trust me when I say that you want this gear.
Nothing in the game is more satisfying than mastering these bosses and getting that drop you’ve been grinding hours for.
So let’s break this down to see which bosses will take countless hours to master, and which will unforgivingly send you back to Lumbridge over and over again.
This giant spider is located just under 30 Wilderness east of the Bone Yard.
With a combat level of 464, she’s no push over.
She attacks with magic and long ranged melee, but it’s recommended to use protection from Magic, as she’ll hit you for very high damage(up to 50) more often without it.
As if taking her down wasn’t hard enough, you’ll also need to contend with Pkers who frequent this spot looking to kill players fighting Venenatis.
Make sure to take a 1-click teleport so that you can make a quick escape should PKers arrive.
Venenatis is primarily hunted for the Dragon Pickaxe and the Treasonous ring, which is a unique drop only obtainable from her. And it’s recommended to only fight this boss at “off peak” times to avoid PKers.
Kree’arra, often just referred to as “Kree” or “Armadyl”, is a level 580 Aviantese located in the God War Dungeon.
As she’s an Aviantese, you can only damage her effectively with range attacks, as melee won’t work, and mage is not effective.
To gain the ability to fight her you’ll either need an ecumenical key, or a kill count of 40 Armadyl followers within the God war Dungeon.
I would recommend getting an ecumenical key as it’ll save you A LOT of time.
You should always try fight Kree while on a slayer task for Avianteses, that way you can get the slayer helmet damage bonus which will make the fight a lot easier.
Going in unprepared is a guaranteed death, as letting your range prayer drop even once can result in taking up to 69 damage.
And Kree is very accurate with her range attacks. Be wary.
Deep under Taverley Dungeon you’ll encounter the level 318 hellhound named Cerberus.
Many adventurers chase this boss in an attempt to get the rare Primordial Crystal drop from Cerberus, which is worth a small fortune.
And Cerberus is a tough fight that should not be underestimated.
He’ll spawn lava pools around the room which will damage you over time, as well as summoning his three guardians which can hit you for 30 damage each if you don’t prayer correctly against them.
It’s very easy to get taken out by the guardians and Cerberus while your attention is focused elsewhere.
Take a lot of high healing food such as sharks and prayer potions, and remember to focus on which prayer should be up.
You might just squeak by with a win.
After completing Dragon Slayer 2, players will earn the right to fight Vorkath, an undead blue dragon with a level of 732.
Vorkath can attack with all three combat styles, as well as three types of dragonfire all with varying effects.
The sheer amount of mechanics here (as well as an “instant kill death fireball”) can make this boss frustrating to learn.
One mis-click will see you dead and back in Lumbridge in seconds.
Vorkath has a very generous drop table with a ton of resource drops aimed at prayer and crafting, making this a great boss to grind as an Ironman.
But this boss should only take a day or two to master.
Now Zulrah is a very tricky boss to learn.
With multiple rotations and attack styles, this level 725 “swamp serpent” is no joke.
You’ll need to learn this boss’ movements and attack styles meticulously. Putting up the incorrect prayer will result in taking a ton of damage. Hell, even putting up the right prayer can still have you taking damage during her mage phase…
Zulrah can be a real nightmare.
Most players who learn Zulrah will die, over and over again. It has a very steep learning curve and is a great entry into high-level PvM content, as it involves learning to switch gear efficiently while praying properly.
Once mastered, this boss becomes very rewarding, as her drop table is generous.
She has even been affectionately been given the nickname of “money snek” by the community, because her drop table is that good.
7. Tz-Tok Jad
Also known as “Jad”, this boss has been infamous for one-shotting more players than any other boss in the history of RuneScape.
You spawn at Jad all ready for a fight, when you suddenly and instantly die to something you can’t even see.
Every veteran Old School player knows all too well how this feels.
To get to Jad you must fight your way through 62 waves of enemies without being able to resupply.
On wave 63 you face the final boss, Jad, and a single mistake is usually punished with instant death.
Jad is all about calm nerves and practice. Be prepared for a fight that truly tests your nerves.
Defeating this boss unlocks one of the best capes in game, the Fire Cape, which is a badge of honor and quite frankly one of the coolest capes in the game.
6. Corporeal Beast
Corporeal Beast, also commonly known as “Corp”, is a level 785…beast, found in a cave just next to the Graveyard of Shadows in level 21 Wilderness. This can easily be reached by using a Games Necklace.
Corp is an insanely tanky boss with over 2000 health, as well as the ability to reduce almost all damage by 50%.
Only spears and halberds ignore this, and as a result, the Zamorakian Spear is often the weapon of choice for adventurers looking to bring Corp down.
Most players opt to fight this boss in teams of 3 or higher, as it is almost impossible to solo this boss without reducing its stats significantly (which can be quite tedious).
Corp is quite popular, though, as it has the very rare chance to drop the Elysian Sigil. And that sigil is worth well over 1 billion gold pieces, making it one of the most expensive PvM drops in the game!
5. The Nightmare
This is a relatively new boss to Old School RuneScape, with a release in early 2020 along with the entire town of Slepe.
She’s a level 814 monstrosity that’s often fought by groups of high-leveled PvMers.
She has multiple phases, attacks, and mechanics, which must all be mastered before you can hope to secure a kill.
It’s very easy to lose focus and get overwhelmed. So keeping an open line of communication with your team over Discord makes things a lot easier.
Also note that fighting this boss is very resource-heavy and will require a lot of Saradomin Brews, Anglerfish, and Super Restores.
Defeating The Nightmare offers you the chance at securing the best crush armor and weapon in the game, The Inquisitors Set, as well as a chance at some of the best OSRS magic weapons like the Nightmare Staff and Harmonised Orb.
4. Corrupted Hunllef
Everything to do with the Corrupted Hunllef is a challenge and a half.
To face this insane boss you’ll first need to enter the Corrupted Gauntlet, which gives the player 7 minutes and 30 seconds to prepare for the Hunllef.
In this time you’ll need to craft weapons, armor, and find enough resources to survive your encounter with this extremely challenging level 894 boss.
The time limit is extremely tight, and even if you manage to prepare in time, you’ll still need to face off against (and defeat) the Hunllef to beat the Gauntlet.
And this is an extremely difficult boss who constantly changes attack styles which must be prayed against. Plus these attacks have a ton of AOE damaging effects such as tornados, which will track you across the room, and can even disable your prayer temporarily.
But the hardest part is that this is a solo boss fight. Meaning no one can help you, you can’t bring any of your outside gear, and you’re constantly on the clock.
This is easily one of the most stressful boss encounters.
3. Great Olm
The Great Olm is the final boss of the Chambers of Xeric, which was Old School RuneScape’s first ever raid.
Olm has an impressive combat level of 1043, and equally high stats across the board.
Most players will need a minimum of three people to take on the Olm, as each player will focus on a different part of its body during the fight.
Like most other high-level bosses, this boss has many different phases and attacks. Which can be chaotic to deal with back to back.
It’s not uncommon to die at this boss, even with the full support of an experienced team.
And like I mentioned, Olm is the final boss before completing a Chambers of Xeric raid, so he’s the guardian of some of the best end-tier equipment such as the coveted Twisted Bow, which has a market value of over 1.2 billion gold pieces.
That’s pretty much enough to set you up for life.
2. Verzik Vitur
What can I say about Verzik?
You’ll die, many times, before you manage to get even one successful kill.
The Theatre of Blood is the second raid in RuneScape and easily the hardest, with Vezrik being the final boss you will face.
Verzik has three phases, with each phase becoming progressively harder. You’ll need to be a master of everything, from switches to counting game ticks, in order to beat this boss with your team.
Finding a good team who can consistently beat Verzik and the Theatre of Blood is a challenge in itself, as this content is not for the faint of heart. You’ll need to be a master of PvM and able to take on all the other bosses listed above with ease before even thinking of attempting to best her.
But defeating her will give you a chance at some juicy loot, such as the best in slot melee weapon: the Scythe of Vitur.
I think everyone who has heard of The Inferno saw this one coming in for the number one spot.
Zuk is the final boss you’ll face at the end of The Inferno, with a massive combat level of 1400, and the ability to one-shot any adventurer too slow to react to its powerful attacks.
However, Zuk is only a tiny portion of the challenge that is the Inferno.
This piece of content is so insanely difficult that most players will probably never even attempt it.
The Inferno has a reputation for requiring insane skills that only the best of the best players have. So it’s fair to say this boss in fits pretty well.
Defeating Zuk will unlock the best melee cape in the entire game, The Infernal Cape.
Not only is this cape absolutely beautiful to look at, but any player wearing it deserves some, respect knowing that they’ve beaten the hardest challenge that OSRS has to offer!