Challenge labs (CTF)
A challenge lab is a capture-the-flag lab: a lab with something hidden in it, and a set of missions that tell you what to go and find. Each mission ends with a flag — a secret string you find by solving the mission and paste back into the dashboard.
By the end of this page you will know how to run a mission from start to flag, what a wrong flag costs you, and how team labs work.
Open the catalog from My Labs → Challenge Labs in the sidebar.
1. Deploy the lab
Each card in the catalog shows the lab's difficulty, whether it is a solo or team lab, and — for event labs — which event it belongs to. Open a lab and deploy it the same way you deploy any lab (see Labs).
Missions only work while the lab is running. If it is not, you will see "Instance is not running, deploy lab to start the mission."
Find a lab in the catalog
The catalog of challenge labs is at /labs/challenge. Use the search box and the
filters to narrow it down:
| Filter | Shows |
|---|---|
| Premium / Free | Labs that need a paid plan, or labs open on the free plan |
| Solo / Team | Labs you play alone, or labs you play with your clan |
| Event | Labs that belong to an event |
| Retired | Event labs that have been reopened for practice |
| New / Partial / Completed | Labs you have not started, labs where you have captured some flags, and labs where you have captured them all |
| Easy / Medium / Hard | Difficulty |
| Category | The subject area of the lab |
Select Clear to remove every filter.
Limits on team labs
A team lab counts against your clan, not against you alone. On the free plan a clan can run at most 3 team labs at the same time. If it already has three, deploying another one fails with "You can only deploy 3 labs at a time in team mode. Please stop a lab to deploy a new one." Stop one of the clan's team labs first.
2. Open the missions
Open the lab and go to the Challenges tab. Each mission card shows:
| On the card | Means |
|---|---|
| Zeal value | What the mission pays at the current multiplier |
| Difficulty | easy, medium or hard |
| completed badge | You have already captured this flag |
| Failed Attempts | How many attempts at this mission failed |
| Score Multiplier | What your reward is multiplied by — select the info icon beside it for the full explanation |
Some missions are locked until you finish the ones before them: "This challenge is locked, you have to unlock it by finishing previous challenges first."
The lab's other tabs include Achievements (badges for this lab) and Leaderboard (who has earned the most from it).
Each card also shows the mission's category badges and a timer while the mission is running. The button on the card changes with the mission's state:
| Button | When you see it |
|---|---|
| Start Mission | You have never started this mission |
| Submit Flag | The mission is running and the lab is running |
| Restart Mission | The last attempt failed, or you have already captured this flag |
| Mission Brief | Always — the story and where to start |
A locked mission unlocks as soon as you capture a mission it depends on. If it depends on several, you need all of them.
3. Start a mission
Select Start Mission. You will see:
The flag is in place, now go capture the flag, time is running.
At that moment a new flag is created for you and placed inside your lab. It is random, and unique to you (or to your team) and to this attempt. Nobody else's flag will work in your lab, and a flag from an earlier attempt will not work either.
Select Mission Brief for the story and hints about where to start.
A lab runs one mission at a time. Starting a different mission — or stopping, redeploying or losing the lab — fails the one in progress. The start dialog warns you if a mission is already running.
4. Submit the flag
When you have found the flag, select Submit Flag, paste it in and confirm.
Correct flag: "Congratulations, you have captured the flag." You earn the mission's Zeal — the first time only — and any missions that depended on it unlock.
Wrong flag: "Oh, no! That doesn't look like the right flag."
You cannot simply try again with a different string. The attempt is marked as failed, your score multiplier for that mission drops by a quarter, and the flag you were hunting is no longer valid. Select Restart Mission to get a new flag and start again.
So check a flag before you submit it — copy it exactly, with no extra spaces.
Flags are a long string of letters and digits ending in .ninja. Spaces before
or after the flag are ignored; anything else must match exactly.
What counts as an attempt
| What happened | Counts as |
|---|---|
| You submitted the right flag | A successful attempt — you are rewarded |
| You submitted a wrong flag | A failed attempt |
| The lab ran out of time while the mission was running | A failed attempt |
Your best reward comes from capturing the flag on the first attempt without hints. Once you have captured a flag, doing the mission again pays nothing, and later failures on it no longer count against you.
How much a mission pays
Three things set the Zeal a capture pays. The Start Mission dialog calculates it for your next attempt before you begin, and the info icon beside Score Multiplier shows the same numbers for the first 10 attempts.
| Part | Rule |
|---|---|
| Mission value | The Zeal the mission is worth before anything else is applied. The figure on the card is what it pays now, with the other two parts already applied |
| Score multiplier | Starts at the mission's own multiplier on your first attempt. Each failed attempt lowers it by 25% of its current value, so it shrinks with every failure but never reaches zero |
| Hint usage | Every Jolt you spend on this mission's hints takes 0.5% off the mission value |
For example, on a mission worth 100 Zeal with a 1x multiplier:
| Attempt | Multiplier | Pays, with no hints | Pays, after 4 Jolt of hints (2% off) |
|---|---|---|---|
| 1st | 1x | 100 | 98 |
| 2nd | 0.75x | 75 | 74 |
| 3rd | 0.563x | 56 | 55 |
| 4th | 0.422x | 42 | 41 |
- Where
- My Labs, Challenge Labs, open a deployed lab, Challenges tab, click the info icon beside Score Multiplier on a mission card
- What it shows
- The score multiplier dialog: the 'What is an Attempt?' and 'What is Hint Usage?' explanations and the table of the first 10 attempts with their multiplier and multiplied Zeal reward.
The reward is rounded to a whole number and paid once, the moment you submit the right flag. Missions in a retired lab pay half.
The Submit Flag dialog mentions a bonus for submitting a mission report. There is no Submit Mission Report button at the moment, so that bonus cannot be claimed. The flag reward is not affected.
There is no extra reward for being the first to capture a flag. Events record who got there first on the event's Trends tab, but it does not change anyone's Zeal.
Hints
Each mission can have hints. They cost Jolt, unlock in order, and each Jolt you spend on hints slightly reduces the mission's Zeal. The unlock dialog shows the cost and how much it reduces the reward.
You have to start the mission before you can open its hints. After you have captured the flag, the hints are free to read.
The Hints card beside the missions lists every mission's hints, with a lock on the ones you have not bought and the Jolt price of each. To buy one:
- Start the mission.
- In the Hints card, open the mission and select the next locked hint — Hint #1 first, then Hint #2, and so on.
- Read the dialog. It shows the hint's cost, your Jolt now and after, and the mission reward after the reduction. Confirm to unlock it.
- Where
- My Labs, Challenge Labs, open a deployed lab with a mission started, Challenges tab, Hints card, click a locked hint
- What it shows
- The unlock hint dialog showing the hint's Jolt cost, the 'Reduces Original Zeal by' line, and the table with Hint Cost, Available Jolt and Jolt Remaining after Unlocking.
| Rule | Detail |
|---|---|
| Order | You cannot unlock a hint until the one before it is unlocked |
| Price | Set per hint, and shown before you pay |
| Reward reduction | 0.5% of the mission value per Jolt spent — 2 Jolt of hints takes 1% off |
| Not enough Jolt | The unlock fails and the hint stays locked. Nothing is taken |
| Paid once | An unlocked hint stays open for that mission, including on later attempts |
| After a capture | Every hint of a mission you have captured is free to read, and reading it does not touch the Zeal you earned |
Time and renewal
Challenge labs run for a set time and then stop. The expiry is shown at the top of the lab page.
To add time, select Renew while the lab is running, choose how much with the slider and confirm — the dialog shows the Jolt cost. A lab can be renewed only a limited number of times.
If no mission is running, redeploying the lab resets its timer for free. Do not redeploy during a mission — that fails it. And if you redeploy after paying for a renewal, the extra time you bought is lost.
Team labs and clans
Some challenge labs are team labs. To deploy one you need to be in a clan with at least two members.
A team lab belongs to your clan, not to you alone. When a teammate captures a flag it counts for them and for the clan, and the rest of the clan is notified.
What the clan shares, and what stays yours:
| In a team lab | |
|---|---|
| Who can open it | Only members of the clan that owns it |
| Missions | One set for the whole clan: one flag per attempt, one attempt count, one multiplier. A wrong flag from any member is a failed attempt for everyone |
| Starting a mission | Any member can. The others are notified who started it |
| Hints | Shared. Whoever unlocks a hint pays the Jolt, and the reward reduction applies to the clan's mission |
| Capturing a flag | The member who submits it earns the Zeal, and the clan earns the same amount as clan Zeal |
| Failed attempts | Every member is notified |
| Achievements | Zeal goes to the member who earned it and to the clan. Any Jolt goes to that member |
If you are not in a clan, deploying a team lab fails with "Lab is in team mode and you are not in a clan". If your clan has only one member: "At least 2 members are required in a clan to deploy team challenge labs!"
Lab achievements
Each challenge lab can have achievements, listed on its Achievements tab. They are awarded automatically when you capture a flag that completes the condition, and each one pays once.
Conditions are set per lab. Typical ones are:
- capturing a particular mission, several missions, or every mission in the lab;
- capturing them with no failed attempts, or without hints;
- capturing a mission within a time limit, or several missions within a set window of each other.
The Achievements tab shows each achievement's name and reward, and marks those you have earned Achieved. Locked ones show a padlock image; the name usually tells you the condition. Rewards can be Zeal, Jolt or both. In a team lab, Zeal goes to you and to your clan, and Jolt goes to you.
Retired labs
When a lab from an event is retired, it stays open for practice. Its missions pay less than they did during the event, and captures do not appear on the event's leaderboard.
In detail:
| In a retired lab | |
|---|---|
| Deploy | Allowed without registering for the event |
| Mission reward | Half of what the mission would normally pay |
| Your total Zeal, league and the CTF Leaderboard | The Zeal you earn counts as usual |
| The event's leaderboard and the lab's Leaderboard tab | Not counted — they only show captures made while the event was live |
Why did that happen?
| What you saw | Why |
|---|---|
| "Challenge is locked" | The mission depends on another one you have not captured yet |
| "Challenge is already started" | That mission is already running. Submit its flag, or start a different mission, which ends this one as a failed attempt |
| "Challenge is already finished" when submitting | The attempt already ended — a wrong flag, the lab stopping or another mission starting ended it. Select Restart Mission |
| "Please start the mission before accessing hints" | Hints open only while the mission is running, or after you capture it |
| My reward dropped and I did not submit anything | The lab expired, was stopped or was killed while the mission ran. That counts as a failed attempt |
| A captured mission paid nothing | You had already captured it. Each mission pays once |
| A flag was rejected but I am sure it is right | Each attempt has its own flag. A flag from an earlier attempt, from a teammate's earlier attempt, or from another player's lab never works |
Leaderboards
- Each lab has its own Leaderboard tab.
- The CTF Leaderboard (Mastery Hall → CTF Leaderboard) ranks everyone by challenges completed, then Zeal earned, then time taken.
How to play CTF challenges in Selfmade Ninja Labs walks through a challenge from start to flag, and the CTF challenges category has write-ups from past Yukthi CTF events.
Next
- Events — timed CTF competitions.
- Clans and clubs — form a team.
- Fair play