Unit 4 · Level 1 · First investigations
Trace a swap end-to-end
A friend messages you a transaction hash: 'I swapped and got a terrible price. Was I hacked??' You have everything you need: an explorer, the five-field scan, and the logs. Time to run a real investigation, start to verdict, using nothing but public data.
Free to play. No ads, no token, no account needed to start.
What you get asked
Run the investigation in the right order
Basics first, logs second, arithmetic third, verdict last. Notice the verdict came from evidence, not from your friend's panic.
The logs show your friend paid 1,000 USDC and received 0.4 ETH. What effective price per ETH did they pay, in USDC?
1,000 ÷ 0.4 = 2,500 USDC per ETH. If the market price was around 2,000, they overpaid roughly 25%: painful, but explainable.
The swap succeeded, tokens reached your friend's wallet, but the price was ~25% worse than market. What's the most likely cause?
Everything went where it was supposed to go. The pool was just thin, so the trade itself moved the price. A tight 'minimum received' setting would have reverted it instead.
Before trading an unfamiliar token, check the pool's ___. A shallow one turns any decent-sized trade into a bad price.
Pool reserves are public like everything else. Trade size versus pool depth predicts your slippage before you ever sign.
What made this investigation trustworthy?
No authority, no vibes: a hash, the logs, and division. Your friend can retrace every step and reach the same verdict. That's the whole craft. 🐜
The rest of this unit
Trace a trade, autopsy a rug pull, stress-test a claim. Detective work begins.