If you’ve opened the Stolen Experiment Vault tracker and seen two separate counters sitting at zero, here’s the short version: Steal an Egg’s Lost Parts are two fixed pickups, one in the Volcano biome and one in the Prehistoric biome, and they don’t move between servers. The other three pieces the vault wants aren’t “lost” at all — they’re Drone Parts, and they only drop from Dr. Scramble’s Experiment Drones during the timed event.
You need all five before Nibbles will open the vault, and below is exactly where each one sits.
Where to Actually Start the Lost Parts Quest
Nothing counts until you’ve triggered the quest first. Head to the Abyss Ocean biome — it’s the seventh zone, sitting right next to Volcano — and follow the rock wall on the right-hand side until you spot a small gap. Step through it and you’ll land in a Secret Cave.
Inside is Nibbles, the Escaped Experiment #013 who broke out of Dr. Scramble’s lab with a damaged machine. Talk to him and sit through his story; once it’s done, the Stolen Experiment Vault panel opens and shows two counters — Lost Parts 0/2 and Drone Parts 0/3. That’s your whole checklist for the rest of this guide.
One small note on accuracy here: some write-ups describe Nibbles as a small mouse, others call him a rabbit-like “Escaped Experiment.” The dialogue and quest are the same either way, so don’t worry if the model doesn’t match what you expected — you’re in the right cave.
Lost Part #1: Inside the Volcano Biome
This is the one most players give up on early, because the part isn’t visible from outside. Go to the small volcano structure near the center of the Volcano biome and actually walk into it rather than circling the outside looking for a glowing item. Once you’re inside, head toward the upper section closest to the wall where the fire is — that’s where the collect prompt shows up.
Players sticking only to the exterior consistently miss this one, and it’s the piece that eats the most time in a blind run. If you’ve walked the whole outer rim twice and found nothing, that confirms you need to go in.
Lost Part #2: Behind the T-Rex in the Prehistoric Biome
This one is faster once you know the landmark. In the Prehistoric biome, find the large T-Rex skeleton or model — it’s hard to miss — and check the left side, just behind its head, near a patch of wires and green plants. Press the collect prompt and your Lost Parts counter should flip to 2/2.
A quick gut-check before you move on: if your tracker still reads 1/2 after grabbing both spots, you’re probably in the wrong biome. Prehistoric sits between Abyss Ocean and Volcano on the map, and a couple of other zones have their own dinosaur-adjacent scenery that isn’t the right one.
The Other 3 Pieces Aren’t Lost — They’re Drone Parts
Here’s where a lot of guides blur two different mechanics together. The Lost Parts are fixed map pickups you grab once and never touch again. The remaining three, called Drone Parts, work completely differently — there’s no map spot for them at all.
Every 30 minutes, a server-wide Dr. Scramble event kicks off and lasts five minutes. During that window, small floating drones spawn in Abyss Ocean and every biome past it. Equip your bat, approach a drone, and hit it — each drone has only a handful of HP, so a few solid swings will pop it. Killing a drone always drops Samples, the event currency, but a Drone Part is a random bonus drop on top of that, not a guarantee. Sources differ on the exact drop odds, and the developers haven’t published a number, so the honest advice is to hit every drone you can reach rather than farm selectively.
| Piece | Type | Where to Get It |
| Lost Part #1 | Fixed pickup | Inside the Volcano biome, upper interior near the wall |
| Lost Part #2 | Fixed pickup | Prehistoric biome, left of the T-Rex’s head |
| Drone Part #1–3 | Random drop | Defeat Dr. Scramble’s Experiment Drones during the 30-minute event window |
In practice, across a few full event cycles, the two Lost Parts took under ten minutes combined once you know the exact spots — the real time sink is always waiting out drone spawns and hoping for the drop.
How Long You Actually Have
The wider Dr. Scramble event — introduced after Ben brought Sammy from Steal a Brainrot into Steal an Egg and Dr. Scramble hijacked him — is confirmed to run until Saturday, September 26, 2026. The vault secret itself has been reported as available for roughly seven days from its release, which lines up with that window. Neither figure is an official patch-note date from the developers, so treat the 26th as the safer deadline and don’t leave both Lost Parts for the final day if you can help it. If the devs extend the event, this section will read differently after that update — as of today, plan around the date above.
What You Actually Get for Finishing It
Completing the vault unlocks a weapon called the Scrambler. Reports differ slightly on the specifics: some describe it as a melee tool that doubles your hits against drones (meaning faster Sample farming), while the in-game reward text has also been described as a weapon that knocks other players back on hit. It’s possible both are true — one triggers when you start the quest, the other on final completion — but that hasn’t been confirmed cleanly across sources, so check the item’s own tooltip in-game rather than taking either description as gospel.
Common Ways Players Get Stuck
- Looking outside the volcano instead of inside it. The exterior has no prompt; you have to actually clip through and stand near the fire section.
- Checking the wrong dinosaur. Prehistoric has more than one large creature model — the part is specifically by the T-Rex, not any other one you pass on the way.
- Ignoring the Lost Parts and only farming drones. Since drone drops are random, players who skip the two guaranteed pickups end up waiting on RNG for all five instead of three.
- Missing the quest trigger entirely. If your tracker never opened, you likely walked past the Secret Cave entrance in Abyss Ocean instead of interacting with it.
Is Finishing the Full Vault Worth It, or Should You Just Grab the Two Lost Parts?
Given that the two Lost Parts cost almost no time once you know where they are, there’s little reason to stop halfway. The three Drone Parts do take longer since they’re tied to the event timer and RNG, but you’re farming Samples anyway during that window — Samples that also go toward shop items covered in our Dr. Scramble event guide, including the Experiment #001 Egg. Chasing the vault and the shop at the same time means the Drone Part hunt isn’t really wasted time either way.
Once the vault is open and the Scrambler is in your inventory, the rest of the event window is better spent on whichever biome targets you’re still missing — whether that’s the Angel Egg, the Eternal Gorilla King, or the Tiger Egg, all of which sit in different zones than the vault route. If you haven’t touched the newer areas past Volcano yet, the Angels & Demons biome added in Update 4 is worth a detour too, and the Steal an Egg Rift Event is the closest comparison if you want another timed secret with a similar two-part structure. For everything else the game has shipped recently, our running list of Steal an Egg updates stays current, and the full story behind why Dr. Scramble is even active traces back to the Sammy Is Coming update.