This article explains how to earn $DFO tokens in Defensio's Scavenger Mine – a 14-day event where anybody can earn $DFO (Defensio's utility token) simply by sharing their device’s processing power to solve cryptographic challenges (also known as ‘mining’).
Miners will share 2,850,000 $DFO tokens daily proportionate to how many challenges they solved that day. The easiest (and most profitable) way to participate is to use the Scavenger Mine feature inside NUFI wallet:
- Faster mining: NUFI leverages your CPU cores to mine faster
- Maximize earnings: Mine with multiple accounts/addresses to earn more $DFO
- Single-account mode: Mine with multiple addresses belonging to one account
- Go back in time: NUFI lets you solve challenges from up to 24 hours in the past
- Consolidate/donate $DFO earned by multiple addresses to one address for easy claiming
- Mobile-friendly: Participate using your mobile device
- Hardware wallets supported: Ledger, Trezor, Keystone and OneKey devices
How to participate in Defensio’s Scavenger Mine
Step 1: Prepare your Cardano account(s) in NUFI wallet
1) Install NuFi’s browser extension wallet or open the web wallet (no download needed; works on mobile devices)
- Create a new wallet; or
- Pair a hardware wallet (Ledger, Trezor, Keystone and OneKey devices supported); or
- Restore your Cardano accounts using a 12, 15 or 24-word seed/recovery phrase.
2) Choose a profile name and password
3) Enable Cardano blockchain; hardware wallet users click ‘Add Account’ and follow instructions to add your device's Cardano account(s)
Step 2: Register and start mining
Click 'Airdrop' on the left side of your wallet and select Defensio. You'll see your Cardano accounts.
Important: you can mine $DFO using multiple accounts or using one single account with 20+ addresses. Each account/address earns its own $DFO allocation.
To mine using one account, enable 'Single account mode' and select the account you want to mine with. You'll see the account's unused addresses displayed below.
4) Click Register, and Sign to complete registration.
Important: when you Sign, you are not signing a transaction and there is no on-chain effect; instead, you sign a message that proves wallet ownership, confirms the destination address, and confirms your adherence to Defensio’s terms and conditions.
5) Click ‘Start Mining’; repeat steps 4 and 5 for each account or address you want to mine with.
Important: your earned $DFO balance updates every 24 hours. Earned $DFO is not transferred into your Cardano account yet; the tokens can be transferred into your wallet when the Scavenger Mine phase ends.
Reassign (aka 'donate') redeem rights from one address to another
You can consolidate the $DFO you've earned from multiple addresses into a single address and - when the Scavenger Mine ends - redeem all your $DFO allocations conveniently with one address. This is done by reassigning redeem rights.
Why Reassign/donate?
When the redemption period begins, you can transfer the $DFO you've earned into your wallet. If you're mining with multiple addresses and you don't consolidate, each address will need to claim $DFO individually and you'll pay transaction fees for each separate claim.
Q: I'm not using NUFI wallet to mine $DFO; can I still use NUFI's donate functionality?
A: Yes - restore your mining wallet into NUFI using a seed phrase or by pairing a hardware wallet. Click Airdrop and select Defensio to see your mining accounts and follow the steps below to donate/consolidate.
Q: I have multiple seed phrase wallets and want to consolidate to one address. Is it possible?
A: Yes; you can restore each seed phrase into its own wallet profile, and follow the steps below to donate to the same external address. To do this:
- Open NUFI and click Restore; enter a seed phrase to restore accounts into a wallet profile.
- Log out of the wallet and click Restore again; enter the second seed phrase to set up the next wallet profile.
- Each time you open NUFI, you can choose which wallet profile you want to log in to.
Reassign redeem rights to an account inside the same wallet
- Click 'Reassign' next to an address
- Choose a Destination Account to receive redeem rights from the Source Address
- Sign the message to confirm
- Done! The Destination Account can now claim the earned $DFO instead of the Source Address.
Important:
- You can reassign redeem rights to a Destination Account in your NUFI wallet that has been registered for Defensio's Scavenger Mine.
- The first registered address of the Destination Account will receive the redeem rights.
- A Destination Account's first registered address may be different from the account's primary address.
- When you select an Destination Account from the dropdown box, its primary address is displayed, but when you Sign the confirmation message, you may see that a different address is receiving redeem rights. This is simply because the account's primary address and first-registered address are different.
- If you see a message saying 'no eligible accounts', this means you're trying to reassign rights from an account's first registered address but there is no other registered account to reassign redeem rights to.
Reassign redeem rights to an external address (e.g. a different NUFI wallet or external wallet)
- Click 'Reassign' next to an address
- Select 'External address' and enter an address that has registered for Scavenger Mine
- Sign the message to confirm
- Done! The external address can now claim the earned $DFO instead of the Source Address
Important:
- You can reassign redeem rights to an external address that has been registered for Defensio's Scavenger Mine.
- If you are reassigning redeem rights to an address in a different NUFI wallet and you want to know which address the account used to register for Scavenger Mine:
i) click 'Airdrop' and find the address to which you want to reassign redeem rights
ii) click Reassign next to the address, then toggle 'Undo Existing Reassignment'
iii) on the next screen, you'll see the address in full (you don't need to complete Undo process)
How to undo reassigning redeem rights
- Click 'Reassign' next to an address
- Select 'Undo Existing Reassignment'
- Sign the message to confirm
This returns redeem rights back to the original Source Address; you can reassign redeem rights again if you want to.
Important:
- reassigning redeem rights is possible until 11:59pm UTC on December 3rd 2025
- NUFI does not display the Destination Account/external address you chose after you've reassigned redeem rights; to see which address you chose, perform the Reassign action again and the message displayed will show you the address that received redeem rights
- if you're using single account mode, each address completes the Reassign process individually
- reassigning redeem rights does not involve a transaction (there is no on-chain activity or transaction fee)
Troubleshooting
'Already has an active donation'
This address has already reassigned redeem rights to another address; to undo/reset it and donate somewhere else, click Reassign > Undo Existing Reassignment.
'Address is the destination of an existing donation'
Another address has already donated to this address, so this address cannot donate. If you want to change this, undo the donation from the first address (click Reassign > Undo Existing Reassignment').
What happens when I start mining?
When you start mining, you’ll see the status ‘Mining’ next to your account or address. This means that your device’s computing power is being used to solve cryptographic challenges. You don’t need to do anything – just keep the Scavenger Mine screen open. A record of your solved challenges is submitted to Defensio’s servers automatically.
Mining = Earning
Defensio's Scavenger Mine runs for 14 days (from November 20th to December 4th 2025) and every 24 hours is its own cycle. In each 24-hour cycle, a new challenge becomes available on the hour, every hour. Your device will begin solving each new challenge automatically (as long as one or more accounts is ‘Mining’ and the Scavenger Mine screen is open).
In each 24-hour cycle, approximately 2,850,000 $DFO tokens will be distributed to participants, proportional to how many challenges they solved in that cycle. Therefore, the more challenges you solve daily, the more $DFO you earn. Over the 2-week event, 40,000,000 $DFO will be shared by miners.
While you’re mining, the Scavenger Mine screen shows you:
- how many solutions you’ve found in your current session. A session is an uninterrupted streak and if you close the Scavenger Mine screen, or close NUFI wallet, or go offline, you’ll end your current session.
- how many challenges are queued up for you to solve; this includes challenges from the current cycle that you missed earlier.
- how many CPU threads you’re using and how many hashes you’ve computed; if you're using the browser extension wallet, you can select how many CPU threads to use.
- when the next challenge becomes available (i.e. when the next hour begins).
- the maximum age of challenges you want to solve
What happens when the Scavenger Mine ends?
When the Scavenger Mine ends, the redemption period will begin. During this time, you can transfer earned $DFO tokens into your wallet. Follow NUFI wallet on X to know when this starts.
FAQs
Q: Do I need ADA in my Cardano account to start mining?
A: No; no ADA is needed in your account in order to mine.
Q: Will tokens 'thaw' like Midnight's $NIGHT token when it's time to claim?
A: No; 100% of your $DFO token allocation will be claimable in one installment.
Q: Can I mine only with an unused address?
A: No - you can mine with an address/account that has been used before.
Q: How many accounts can I use to mine/solve challenges?
A: There’s no limit to how many Cardano accounts you can add to your wallet and mine with, but bear in mind:
- you can’t add a new Cardano account until the previous account has been used. To use an account, transfer 1 ADA into it (you don’t need to transact with the account: simply receiving ADA into it is sufficient).
- adding many Cardano accounts to one wallet profile may impact performance; we recommend limiting the number of Cardano accounts to 10 accounts per profile.
If you want to mine with multiple addresses, we recommend using 'Single-account mode' as this does not require adding multiple accounts.
Q: Do I need to have participated in Midnight's Scavenger Mine to take part?
A: No; no prior participation in an event is required to take part in Defensio's Scavenger Mine.
Q: What happens if I close the Scavenger Mine screen?
A: If you close the Scavenger Mine screen, you stop mining. Completed challenges are not lost because these are recorded and submitted to Defensio automatically upon completion. You can resume mining immediately by opening the screen again.
Q: How can I stop my wallet from logging out automatically?
A: Go to wallet Settings and set auto-logout to 'Never'.
Q: Can I use my mobile device to mine?
A: Yes; NUFI’s web wallet can be accessed using any browser on mobile devices.
Q: I restored my existing Cardano account but I don’t see it in my wallet. Why?
A: NUFI may have added a different account than the one you used in other wallet interfaces. Click Add Account (on Accounts or Assets screen), then follow instructions to view other accounts that can be added.
Q: I was offline for a few hours and missed challenges; will I still be able to solve them?
A: Yes; NuFi allows you to solve older challenges as long as they are still valid (up to 24 hours in the past).
Where can I get help?
Open a ticket in NUFI’s Discord server here or create a support ticket here to get help by email.