Boss Mastery is the long-term progress track tied to the Dr. Scramble event in Steal An Egg. Every time you defeat Dr. Scramble’s Mech, your Mastery count goes up by one, and eggs and pets unlock at fixed kill thresholds along the way. The 50-kill point sits in the middle of that track and hands over a Cosmic-rarity pet, the Uncoiled Armadillo.
Quick answer: Each Dr. Scramble’s Mech kill is worth 1 Boss Mastery. Reaching 50 kills unlocks the Uncoiled Armadillo, a Cosmic pet that generates $1.2M/s, alongside every unclaimed egg and pet from earlier milestones.
The Dr. Scramble Mech boss and how kills are counted
Dr. Scramble’s Mech is a timed boss that appears roughly once every 30 minutes. A portal opens that you reach by running through the biomes toward the Cosmic zone, and the fight itself is multi-phase. You break down the mech, expose and destroy its core, then land the final hits on Dr. Scramble himself.
Between spawns you wait in the safe zone and watch the countdown on the Boss Mastery menu. When the timer hits zero, a server-wide announcement confirms the boss has started.
Clearing the fight rewards 1,750 Samples and adds one kill to your Mastery total. Samples are the currency you spend in Dr. Scramble’s Experiments shop, while Mastery is what unlocks the reward track. Everyone who takes part in the fight earns one Mastery per kill, so joining a full server clears the boss faster.
The Boss Mastery reward track
Rewards do not drop from the boss directly. They sit at kill thresholds on the Mastery track and stay unclaimed until you open the menu and collect them. The five headline milestones each hand over a named, indexed pet at a set kill count.
| Kills | Pet | Rarity |
|---|---|---|
| 10 | Eye Bat #021 | Legendary |
| 25 | Citadel Snail #007 | Mythic |
| 50 | Uncoiled Armadillo | Cosmic |
| 75 | Mecha Chompa | Secret |
| 100 | Five Coiled Experiment Armadillo | Eternal |
The kill counts in between those pets pay out eggs rather than finished pets. Both plain and mutated (Scrambled) versions appear across the track.
- Biohazard Egg and Scrambled Biohazard Egg
- Experiment Egg and Scrambled Experiment Egg
- Unstable Egg and Scrambled Unstable Egg
What the 50-kill reward gives you
The 50-kill mark is the halfway point of the track, and the menu confirms it by showing Current Mastery 50 with the 50-kill reward card ready to claim. The reward at that threshold is the Uncoiled Armadillo, a Cosmic pet.
The Uncoiled Armadillo earns $1.2M/s, a modest return compared with other pets in its lineup, so its Cosmic tag is more notable than its income. The earlier Citadel Snail #007, awarded at the 25-kill milestone, earns $25M/s despite its lower Mythic rarity; it has a fortress-like shell that drips purple goo and a “007” marking that nods to James Bond.
The higher tiers scale up sharply. The 75-kill Mecha Chompa is a Secret pet, and the 100-kill Five Coiled Experiment Armadillo is an Eternal, the top of the track.
Turning claimed eggs into pets
Claiming eggs from the Mastery track does not hatch them. They land in your inventory first, and the Growing Eggs panel is where you push them into the growth stage before hatching becomes possible.
The eggs are then placed onto the soil patches inside your personal pen, where they grow on a timer. Only once they have finished growing can they be hatched into pets.
Spending Samples in Dr. Scramble’s Experiments
The Samples you earn per kill feed into Dr. Scramble’s Experiments shop. The standout purchase is the Scrambled Mutation, which you attempt to apply to an egg for a stat boost. The rest are timed boosters.
| Item | Cost |
|---|---|
| Scrambled Mutation (+1–10%) | 475 Samples |
| 2x Cash Booster (10m) | 275 Samples |
| 1.25x Speed (5m) | 375 Samples |
| 2x Treadmill Booster (10m) | 375 Samples |
A Scrambled Mutation is applied to eggs that are still growing, so it stacks onto the milestone eggs before they hatch rather than onto finished pets.
Once your Mastery counter reads 50 and the reward card has been claimed, the milestone is done. From there the track keeps counting toward the 75-kill Mecha Chompa and the 100-kill Five Coiled Experiment Armadillo, so the same 30-minute boss loop carries you the rest of the way.
