Trunk Line (Arkai)
Ping pairs of stations to learn how many hops apart they are, and trace the four hidden lines.
Every day: Three hidden networks every day, the same for everyone, each a tree of four lines joining five stations, with earlier days still playable. New puzzle: Midnight, local time (the day's networks are worked out on your device from the date).
Trunk Line is a daily deduction puzzle on Arkai. Five stations are joined by four hidden lines; ping any two and you learn only how many hops separate them. Work out the true wiring, mark the four lines and check, using as few pings as the par. Three networks a day, the same for everyone.
About Trunk Line (Arkai)
Trunk Line is one of the daily deduction puzzles on Arkai, a small portal of free browser games with no account, ads or third-party code.
Each day brings three networks, Line 1, 2 and 3, with the same rules and difficulty, worked out from the date so every player gets the same ones. Behind a switchboard, five stations labelled A to E are connected by a random tree: exactly four lines that link all five, with no loops.
Ping any two stations and the switchboard tells you how many hops apart they are along the hidden wiring, never which stations the path passes through. A distance of one means a direct line, and the game draws it for you; asking the same pair again is free. Switch to Mark mode to add lines you have deduced without pinging, then press Check. Every new ping costs a point and a wrong check costs two, and matching the par, which is what Arkai's own solver needed for that network, earns a star. Results can be shared without spoilers, and every earlier day stays playable.
It is a compact puzzle about graphs and distances. It suits players who like pure logic with very few moving parts.
How to play Trunk Line (Arkai)
- Open Trunk Line and pick one of today's three networks.
- Tap two stations to ping them and read how many hops apart they are.
- Use the distances to work out which pairs must be joined directly.
- Switch to Mark mode and mark each of the four lines you have deduced.
- Press Check once all four lines are marked, aiming to stay within the par.
Tips
- Five stations with four lines means every station is reached and there are no loops.
- A station at distance one from many others is likely a hub in the middle of the tree.
- Re-asking a pair is free, so jot down nothing: the board remembers your pings.
Questions
Is it the same puzzle for everyone?
Yes, the three daily networks are the same for all players.
What does a ping tell me?
Only the number of hops between the two stations, not the route.
Can I play earlier days?
Yes, every earlier day stays playable, though not for your streak.
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