GhostSalt
META

The Bow

Solution

To solve the puzzle, you'll need these feeder answers from other puzzles:

Puzzle Feeder Answer
Blankety Blank OVERT
Cognition PLAYER
Gang Signs VELVET
Grand Speeches DRAPE
Mots de Passe FONDU
Pride in Purple IBERIA
Puzzling Grids OBLIGE
Start and Finish SWELL
The CRT TV BACKUP
The String CHANCE
Warnings ICHOR

The flavour text hints at HTML source code, which can be looked at by pressing CTRL + U.

The source code of this puzzle has a comment at the bottom, which hints that "you'll find them eventually". In fact, "them" refers to comments in other Puzzle Parcel puzzles. Each of these comments has a number, which will be used later.

The label of the parcel has a 5×5 grid and a 6×6 grid, alongside a +4. We also have 11 feeder answers; five 5-letter words and six 6-letter words. They seem like they could fit into the grids, but in what order?

This is where we use the numbers we found earlier. The 5-letter and 6-letter words can be sorted according to their comment numbers and can now be put into the grids.

O V E R T
S W E L L
I C H O R
D R A P E
F O N D U
O B L I G E
P L A Y E R
I B E R I A
C H A N C E
V E L V E T
B A C K U P

We could try reading the diagonals of the grids, but we get nonsense. However, we still have the +4 to work with.

By Caesar shifting the letters in the diagonals by +4, we get the answer to the puzzle.

SALTY SPIRIT