Sins of the Father Boss guide OSRS [2022] – best tips and tricks

The sins of the father boss, Vanstrom Klause, are among the most challenging quests monsters in OSRS. Generally speaking, medium-level accounts will struggle very hard fighting this Boss. There are a ton of mechanics to take into account, and the Boss hits complex and high. 

This guide will help you with tips and tricks to defeat the sins of the father boss, even if you are not maxed combat. However, do remember that you might have to do this fight a couple of times over to get the hang of it or be lucky enough to take damage and hit Vanstrom Klause. 

Who is the Boss in the Sins of the Father quest

Vanstrom Klause is a powerful vampyre noble that is one of the loyal henchmen of Lord Drakan. Klause is also the leader of the vyrewatch. He is a pretty recent addition to Old School Runescape and is an exclusive OSRS boss monster. 

Let’s look at his stats and draw some conclusions from this that will help in the fight.

Combat levelLevel 459
Max hit24
Attack styleMagic
Hit Points750
Attack speed3.0 seconds
Sins of the Father Quest boss stats
blood orb sins of the father boss

While the boss in Sins of the Father has a lot of hit points and a high combat level, Klause only has a max hit of 24 and an attack speed of 3.0. Those two factors are helpful to consider to make sure you don’t lose any attacks by eating too much food. 

Vanstrom only attacks using magic. That means you should have armor that protects you from magical attacks. 

Now, this does not paint the complete picture. The boss has strong special attacks, which can land you in trouble. The monster is also immune to the ring of recoil and the thralls. 

Sins of the Father boss mechanics and strategy

Vanstrom Klause has a couple of special attacks and immunities that make him a worthy opponent for any player. We will discuss all of these here. In addition, we will discuss the most optimal way of dealing with the Sins of the Father boss’ mechanics, ensuring you take as minor damage as possible. 

Special attacks

The strategy to beat Vanstrom Klause in OSRS is to know the special attacks and learn how to deal with them. 

The Sins of the Father boss will shout out the attack he will use. These are the phrases he will shout and what to do when the spell is used. 

My Pets will feast on your corpse

When the boss uses this attack, Vanstrom will summon the Acidic bloodveld. You must keep your distance. If the bloodveld can reach you, you will take 40+ damage. If you have knives in your inventory, you can use them to kill the bloodveld by just hitting it once. 

After the explosion, there will be a couple of acid pools. Do not step in those as they will damage you. 

boss fight sins of the father osrs

Stare into darkness

The Stare into darkness attack is one you need to look out for. You need to click away fast to look away from Vanstorm, or you will take 40+ damage. If you are not experienced, you will need to count the attacks. Make sure you are quick enough and turn off your auto retaliate. The attack also hits for 40+ damage if he manages to hit you. 

osrs sins of the father boss fight

Blood will be my strength.

The Blood will be my strength; a special attack is quite interesting. This will summon a blood orb that has a size of 3×3. Vanstrom will hit more with his magic when the orb is summoned, even if you are using a protection prayer. There are a couple of ways to deal with this attack:

  • Get hit by the orb and take 30 damage
  • Ignore the orb and tank the hits
  • Lure the orb to Vanstrom and hit him with it

The latter strategy is the optimal play. 

These are the three special attacks the final boss of the sins of the father quest will use. The special attacks are in random order but occur after 8 to 10 regular attacks. 

Immunities and powers

The sins of the father boss have a couple of strong immunities, which make this fight even harder than you would expect it to be. He also has the power to hit through protection prayers, so you will get hit here no matter what you do. 

Vanstrom Klause has the following immunities and thus takes no damage from these attacks: 

  • Poison
  • Venom
  • Thralls 
  • Recoil damage

Tips for medium-level players

Always protect from magic – Keep your magic prayer up and wear gear that defends against magic as well as possible. One of his magical attacks has the annoying side effect that it heals him a bit for the damage he has dealt with you. Vanstrom Klause also has a magic attack that drops your attack levels.

Watch your hit points – Vanstrom hits through your magic prayer. However, the damage is reduced by 50%. That means his max hit becomes a 12 and not 24. This reduction gives you the ability to time your eating more efficiently and makes you lose fewer ticks.

Use your prayer – It can not be stressed enough how important it is to boost your damage with prayers like piety or ultimate strength. These will give you enough power to hit through the boss’s defense and get the kill done much quicker.

Bring knives for ranging – During the fight, the boss will summon Acidic Bloodvelds, who can explode when they reach you. These bloodvelds do 40+ damage if they can hit you. So take a ranging weapon with you. 

Count the attacks – Vanstrom will use a special attack after 8 to 10 regular attacks. So if you count them, you can be prepared for his attacks before they land. 

Gear and inventory for Vanstrom

This picture is the minimum gear I would recommend medium and high levels to wear. If you have better items in the slot, bring those with you. Having this gear, or better, is essential to finish off the boss quickly.

The inventory for the final sins of the father boss that I would recommend is the following.

Osrs sins boss of the father quest

It is essential to take high-level food, divine combat potions, and enough prayer potions to make the fight easy. Often players don’t get killed by the special attacks or a high hit but by simply running out of food. 


The final boss of the Sins of the Father Quest is not to be underestimated. If you are level 90 or below, you will struggle pretty hard, even when using the optimal gear and tactics. You will need to get the mechanics down pretty well and use the best food available. 

Often, you will need to prepare for at least five tries and often more till you manage to kill him. Make sure you give yourself all the options available to you. Use the best possible prayer you have to increase the damage output, and use the BIS gear you can afford to both hits accurately and defend yourself from getting damaged by him. 

fight vanstrom klause

SotF boss FAQ

What gear should I wear during the Sins of the father boss fight?

You should bring the gear that offers you the best magic defensive bonus. Try to find a balance between defending against magical attacks and dealing damage to the boss. A good medium setup is Karil’s armor. 

What should I pray against Vanstorm Klause? 

You should always pray to protect from magic during the boss fight in the Sins of the Father quest. Vanstrom Klause only attacks with magic-based attacks. However, he can hit through prayer. 

What are the recommended levels to beat Vanstrom Klause?

A combat level of 110 is a good starting point to make sure you effectively kill the boss. However, you can beat the boss at level 90 or even lower, but you will need to be lucky with your hits, have good gear, and have a high magic defense. 

Jack Huang

Leave a Comment