Unlike typical boss fights, your hitpoints are not a concern here; your skill levels for Fishing, Hunter, Mining, and Woodcutting are. When you are hit by one of Croesus' attacks, it will drain those skill levels. There will be a purple bar above your head that indicates how drained your stats are. Should the bar completely empty, you fail the encounter and have to start over. This is not considered death; you won't lose any items.
Croesus will only use three different attacks listed below. Whenever one is coming, Croesus hunches down and tenses. If you move when you see this happen, you can avoid most of the attacks. In addition, the Crystal Mask spell will block any stat drain from a Croesus attack, but be consumed in the process. As such, you will need to recast it whenever you get hit. The attacks she will use are as follows:
- Spore bombs: A large ball of spores will erupt from Croesus and land where you are standing. You have a short window to move before the cloud it leaves behind it starts draining your stats. The cloud's color will indicate which skill level it drains: Green for Fishing, Blue for Hunter, Yellow for Mining, and Red for Woodcutting. The cloud dissipates after about 10 seconds.
- Hard Fungus Fall: A purple and white fungus will fly from Croesus and land where you were standing when she threw it. If this hits you, it will cause you to be stunned. If you are still stunned a short period after it lands, it will drain the stats of all 4 relevant skills. Use Anticipate to not be stunned, move from your current location when she throws, or use Freedom if you are hit.
- Slime Mould: An orange and yellow slime mould will land near you and run after you. It can be blocked by terrain, but also is able to hit you diagonally through terrain, so keep your distance. If it reaches you, it will drain the stats of all 4 relevant skills. Once it drains your stats, or after about 6 seconds, it will dissolve.
If you have defeated Croesus before, read from here to the end of the step before continuing.
Once you pass the barricades, Croesus will start attacking you. Each attack (listed above) will land about 13 seconds after the previous one: Green spore bomb, Blue spore bomb, Slime mould, Red spore bomb, Yellow spore bomb, Hard fungus fall, repeat from the start. To complete the encounter, you ONLY need to deplete the mutated fungi skilling nodes found within the area around Croesus. You will not gain any items for this, so inventory space isn't an important consideration. Should you deplete one of the nodes and then fail the encounter, it will remain depleted; you will not have to deplete it again. Note that she does not have an enrage bar, so you will only fail if your purple bar empties.
When all the nodes are depleted, Gorvek will thank you and tell you to ask Saradomin where you should help next.
At the path to the Iaia world gate, speak with one of your allies. After the dialog ends, head North and speak with Seren. She is calling the Elder gods to Iaia. When done chatting with her, return to your group and speak to one of them. Vicendithas will suggest slowing Seren down to help complete the evacuation by using the Needle shards. He will highlight where to place the shards and the rest of the group will finish the evacuation. Move to one of the places marked on the map, place a Needle shard with a left click option, move into one of the other marked spots and ready yourself for combat: as soon as you place the second shard, your fight will begin and you will be boxed in away from the places the shards need to be placed.
Fight Details: The First Phase
You will be fighting several level 120 Shadows with 500 hitpoints, a level 175 Dark lord with 10,000 hitpoints, and a level 175 Light lord with 10,000 hitpoints. The Shadows attack with melee and the two lords attack using Magic. You will not be able to damage either of the lords directly.
Focus on killing the Shadows. Each time one is killed, you will receive a Light core (Extinction). Once you have it, you can attack the Light lord. This will consume a Light core and deal 1,000 damage to it. Not long after you kill the Shadows, the Light lord will summon 2 more: rinse and repeat this process to collect and use 10 Light cores on the Light lord to kill him.
Once the Light lord is dead, 2 Unstable rifts will appear. You will be able to move these like the boulders in Erebus. Left click them and then left click close to the Dark lord and they will slam into him, dealing 2,500 damage. You will need to do this 4 times to finish him off. Once it's gone, you can teleport out to regear before the next phase. Continue the quest by going to the World Gate, talking to an ally, and then walking through the gate. If you choose to not leave and regear, simply speak to Seren to progress.
Fight Details: The Second Phase
Place another Needle shard to start phase 2. Seren will summon a Vestige of Mah, a Mah wisp, and 3 Muspah at a time: one Bladed, one Force, one Throwing. Your goals are to avoid attacks from the Vestige of mah and destroy the Mah wisp (60,000 hitpoints), but it is only vulnerable while no Muspah are present. When all the muspah are dead, you will have roughly 7.5 seconds of time to hurt it before more muspah show up. Note however that this timer doesn't start until you actually damage the wisp! The muspah initially spawn as level 120 with 20,000 hitpoints, but each time more appear, they get stronger and stronger, gaining 50 levels and 5,000 hitpoints. Using AOE to hit as many Muspah at at time is advised.
The Vestige of Mah is mostly something you can ignore with the right positioning. It has three attacks detailed below. It does not perform its attacks quickly, so you will likely see no more than 4 attacks in each wave of muspah.
| Attack | GIF |
| Fire Slam: The Vestige of Mah slams one of its arms to the ground. Doing so causes a wave of fire to erupt from the ground on one half of the arena, North or South, depending on which arm it uses. Should you be standing close to the fire at any point it will deal magic damage equal to roughly 10% of your hitpoints. To avoid this, simply stand close to in line with the Mah wisp so that you can easily move to the North or South half of the field without much effort. |  |
| Lava Spew: The Vestige of Mah opens its mouth and spits forth small flaming projectiles. These attacks deal typeless damage equal to roughly 20% of your maximum hitpoints. However, the projectiles do not appear to land in any particular pattern, hit the ground one at a time, burst shortly after landing, and do not seem to hit the same square twice. By standing still when this attack happens, you significantly reduce the odds of getting hit by it multiple times. |  |
| Lightning Strike: The Vestige of Mah calls down Lightning. It always strikes fairly random, like the Lava Spew, but it does have animations that make it possible to dodge if you are fast enough. Simply use surge, or move away, if you see yourself in the area it's about to strike. |  |
Once the Mah Wisp is destroyed, you have reached a checkpoint and can teleport out to regear for the final phase if necessary. Continue the quest by going to the World Gate, talking to an ally, and then walking through the gate. If you choose to not leave and regear, simply speak to Seren to progress.
Fight Details: The Third (and Final) Phase
For the last phase, it's highly recommended to use melee with dual wield weaponry, or with Laceration boots for this phase, as Bladed Dive and a shield significantly increases your chance of surviving. In addition, your damage output is a minor consideration at best. You should focus more on your mobility and how much food you have at your disposal.
Place another Needle shard to start the last phase (interestingly, you won't successfully plant this one). Your goal in this phase is to survive for 2 minutes.
Seren will summon remnants of herself on the North and South sides of the arena. Every few seconds, Seren will say, "Fire!" and whichever remnant you are in line with will create a line of purple fire going the full North-South length of the room, about 3 squares in width. Standing in the fire will deal roughly 2,700 magic damage to you regardless of most defensive abilities. The easiest way to handle this is by standing in line with one of the remnants and moving into line with another every time she tells them to fire.
After this has gone on for about 20 seconds, Seren will stop having the remnants fire and instead move the Elder God Eggs into the arena. They will move about somewhat randomly, creating shockwaves around them every few seconds. These shockwaves do about 3,000 magic damage, but that damage can be used to heal using the Resonance ability or blocked entirely using the Devotion ability while Protect/Deflect magic is active.
Once the eggs have been moving about for awhile, they will start to summon aspects that attack you with magic. They have 1,500 hitpoints and can mostly be ignored in favor of avoiding the eggs, but they also present you with a few extra ways to avoid the eggs: by using Barge on one of them, you have an additional movement ability and if you kill one of them with Bladed Dive, the cooldown on Bladed Dive is reset. Focus on avoiding the eggs by Bladed Diving into the aspects. This will keep the amount of them to a manageable number and help keep you away from the eggs.
After the aspects have been present for a little while, Seren will have her remnants start firing again. This doesn't change your strategy much, you just will have fewer places that you can stand and you won't be able to stand still as long. Once 2 minutes have passed, Seren will announce that the Elder gods are here and stop bothering you.
