Pebble Post
Two parcels leave. One parcel arrives.
Select a post with at least two parcels, then a connected post. Every crossing spends two parcels and delivers one. A star needs at least one parcel. Plan before you spend!
Why one hop can cost so much
One parcel two edges away costs four at the starting post: two crossings make two parcels at the middle post, then one more crossing delivers the last parcel. Do not empty a starred post unless you can restore it.
The first six networks have two-way lines. Later networks have arrows: follow their direction. Undo is unlimited. A route clue suggests a legal step on a shortest remaining solution; if you spend too much, undo or reset.