Starscourge Radahn is one of the most interesting and unique bosses that FromSoftware has ever created. Aside from his unprecedented character design, Radahn also possesses some very special boss mechanics that are unlike anything veteran Souls players have ever seen before.
Although he is an optional boss, many Elden Ring players consider defeating him to be a crucial part of their playthrough, as doing so unlocks extra content and side quests. Radahn should never be the first Shardbearer you fight, so it is highly recommended to complete Stormveil Castle and Raya Lucaria Academy before attempting to defeat him.
By the time you reach Radahn, you should be at least level 65. He is notorious for being one of the most difficult mid-game bosses, but luckily there are many different things that you can use to your advantage to defeat him.
Summoning Phantoms
Summoning NPC and player phantoms for a boss fight is certainly nothing new in the Souls series, but for the first time players can summon an entire army to back them up. However, you'll need to make a very tough decision before you begin the fight. While it's usually a no-brainer to bring along some friends for a tough battle, engaging Radahn alone actually provides you with a unique advantage. If you don't bring any friends with you, then you are able to ride Torrent during the battle.
This can be immensely helpful for winning the fight if your character specializes in magic or archery, but you still may prefer to fight alongside your companions. Another important piece of information is that if you do decide to use Torrent during the battle, you can still utilize the eight NPC phantoms that are summonable throughout the arena. It is highly recommended that melee characters summon player phantoms before the fight, as Torrent won't be as useful to you if you're not using ranged attacks.
Once you've made your decision about whether or not you want to use Torrent, you can go ahead and begin the fight. After you teleport into the boss arena, you will see an array of glowing summon signs scattered across the vast dunes where the fight takes place.
You should make a point of summoning all the NPC phantoms as quickly as you can, but be warned that Radahn will start launching a variety of ranged attacks the very moment you set foot in his domain. Be aware that you can re-summon defeated NPC phantoms throughout the fight, as they will almost certainly die at some point during the battle.
Phase One
It's important to understand how to deal with Radahn's various attacks, as this fight can be a test of patience and any mistake can be very costly. As soon as you begin the battle, you will need to be ready to dodge his initial wave of attacks. Mere seconds after teleporting into the arena, Radahn will start charging a homing arrow that is likely to kill you in one hit if you don't know how to deal with it.
Homing Arrow
One option is to block the arrow with a shield, but you will still take a significant amount of magic damage and end up wasting a Flask of Crimson Tears early on in the fight. The arrows have a large amount of tracking, so you will likely still get hit by the attack even if you sprint sideways at the beginning of the fight. If you're using Torrent you can summon your mount right away and dash sideways, but the arrow may still hit you.
The best option is to roll through the arrow at the last second as it is hurtling towards you, but this will require a great deal of timing. The easiest strategy for dodging the arrow is to roll toward it rather than away from it, even though this may seem counterintuitive. Alternatively, if you can find a large sand dune or some destructible debris, you can hide behind it to save yourself.
Arrow Barrage
After one or several homing arrows, Radahn will launch a continuous arrow barrage that will follow you around the arena. If you're using Torrent during the fight, you can hop on your mount and dash sideways until the arrow barrage finishes falling from the sky. If you need to escape on foot, your best option is to run backward. Run directly away from Radahn, and keep running until the attack ends.
Arrow Blast
He may also shoot an arrow blast at you, but he often waits to use this attack until you start getting closer to him. Similar to his other ranged attacks, your best option for dodging this is either riding Torrent sideways or rolling toward it at the last second.
If you've survived the initial arrow barrage, you can start making your way toward him while dodging any homing arrows he may decide to fire at you. Make sure to summon all the NPC phantoms you can as you approach him, as he is very difficult to engage by yourself at melee range. When you finally reach him, he will pull out his massive pair of Starscourge Greatswords and begin to attack you with fast, hard-hitting melee attacks.
Phase Two
If you're playing a ranged character, you can allow your Spirit Ashes or phantoms to distract him while you keep attacking from a distance. However, it is still recommended to force him out of his ranged phase as quickly as possible.
Basic Attacks
Radahn will utilize a combination of quick stomps, downward strikes, and wide sweeps with his swords to try to catch you off guard. Luckily, his immense size causes him to heavily telegraph all his moves. When you see him winding up for a swing or a stomp, simply roll behind him and deal some damage to him while he's still recovering from his attack.
Spinning Slash
He often begins his melee phase with a few consecutive spinning slash attacks, so you'll want to get ready to roll away from him when you see him winding up his attack by holding both swords behind his head. Be sure to keep dodging this attack until he stops attacking, and then you will finally be able to deal some damage to him. As with all his melee attacks, you can use Torrent to get away before dashing in for some quick hits, or allow your summons to tank him for you.
Jump Attack
He will occasionally follow up his slash attacks with a jump attack, but this move will be much more telegraphed. Radahn will easily one-shot you if he hits you with it, so make sure to time your dodge correctly and wait to roll until he is swinging his swords down toward you. Alternatively, you can start running away from him as soon as you see him preparing to do a jump attack.
Charging Slash
If he rides away from you on his horse, don't chase after him because it means he is preparing to dash toward you and attack with a series of extra-deadly slash attacks. Either ride away from him on Torrent or be prepared to dodge his attacks with very precise timing, as getting caught once will allow him to combo you with his subsequent attacks. As with his basic spinning slash attack, try to roll away from him until you are out of his reach and wait until he finishes his combo.
Gravity Magic
When you see Radahn clap his swords together and then slam them into the ground while they begin to glow purple, it means he is buffing his swords by using his gravity magic. He will launch into this attack very quickly, and if he targets you with it at close range then your only option is to dodge it. After avoiding the attack, keep rolling or run away because he will try to hit you a second time when he pulls his stone-covered swords out of the ground.
Gravity Slam
After Radahn has used his initial gravity magic attack, he will also start to use a gravity slam attack. If Radahn claps his blades together and pulls you toward him while his swords begin to glow, it means he is preparing to slam his swords into the ground and use a massive AoE attack. Your best bet is to run away as soon as you see him doing this, as your only other options are rolling through it, jumping over it with Torrent, or positioning yourself far behind him.
Gravity Wave
If you are fighting him at range, his repertoire of gravity magic will also include a gravity wave attack. He is capable of following up his basic attacks with this move, but sometimes he will chase after you with his swords crossed before leaping into the air to use it. You can either roll through it, or jump over it with Torrent.
Keep dodging his attacks and sneaking in some hits when you can, and eventually, he will jump into the air and briefly pause the battle. If he does this, it means that you are entering the third phase of the fight.
Phase Three
As soon as he's in the air, you may feel like you finally have a moment to breathe. Don't be deceived, as Radahn is about to come hurtling toward you from the sky.
Radahn's Comet
To avoid this attack, it will help if you look up and around until you see what appears to be a fiery comet crashing down from space. Whether you're on foot or riding Torrent, run away. Wherever he lands, he will create a fiery AoE blast that will almost certainly kill you. Try to quickly predict where he will land, and get away as fast as you can. The best strategy is to start running as soon as he jumps into the air, as this will make it harder for him to predict where he should land in order to hit you.
Once he's back on the ground, you'll want to reengage him and adapt to his new move set. If a significant portion of your summoned phantoms are dead, this is also a good opportunity to run around and re-summon them before attacking him. He will still use all the same attacks as he did in Phase Two, so be prepared to dodge more spinning slashes.
Gravity Pull
You'll also need to worry about his gravity pull attack in this phase. He will telegraph this move by holding his hands in the air and summoning several purple orbs that will fly toward you. To dodge this, you should run sideways on Torrent or roll sideways several times before they hit you. If you get caught by the orbs, you probably won't be killed by the damage from them, but the follow-up attacks will be deadly. To counter this, start rolling away or use Torrent's dash immediately after being pulled toward Radahn so that you can create distance from him as soon as you can move again.
Gravity Defense
He will also initiate his gravity defense move by using a jump attack that causes the ground to glow purple. When he does this, he is about to summon glowing purple rocks that will hover over his head for a significant period of time before launching toward you. He will try to lull you into a false sense of security before attacking you with the rocks, so watch out and don't get comfortable until the rocks aren't floating above him anymore.
As long as you have mastered your counters to his Phase Two attacks and you are able to deal with his additional gravity magic attacks, then you will be able to survive Phase Three and claim victory over Radahn. After his defeat, you will earn the Remembrance of Starscourge Radahn, which will allow you to choose either the Starscourge Greatsword or the Lion Greatbow for your reward. Additionally, you will unlock the ability to purchase his stylish armor from Enia in Roundtable Hold.