### Swivelling Serpents [Birthday Surprise] by Prasanna Seshadri

*(Note: This bonus puzzle is being posted today to mark the occasion of Prasanna’s birthday.)*

**Theme:** One Away from Thirty

**Author/Opus:** This is the 180th puzzle from our contributing puzzlemaster Prasanna Seshadri.

**Rules:** Locate two snakes in the grid. Each snake must start from one of the gray circles, but has an unknown ending point. Black circles represent an interior cell of one of the snakes, and all black circles must be part of a snake. Each snake’s path is allowed to move vertically, horizontally, or diagonally between cells. An interior snake cell can only be adjacent to two other snake cells (including diagonally adjacent cells) and an end of the snake can only be adjacent to one other snake cell (including diagonally adjacent cells). The two different snakes must not share any adjacent cells.

There are some numbers outside the grid. These numbers indicate the number of vertical or horizontal edges (not corners) that snakes cross in that direction.

There are some letters inside the grid. For each distinct letter, exactly one of its instances is visited by one of the two snakes.

Also see this example:

**Solution:** PDF