Investigate Relics

In this puzzle, we are given a series of unlabelled diagrams. The last diagram contains mappings from letters to numbers, so we can surmise that each letter represents a word or phrase that is consistent throughout all diagrams, and the numbers are indices into these words.

There are several possible break-ins for this puzzle, but the most common one is the diagram labelled "B". The first 2 columns contain a list of things whose names differ by numbers (the first is unlabelled, subsequent ones are labelled 2 and 3). This naming is reminiscent of video games or movie franchises. This hypothesis is further strengthened by the use of colons in the third column. Eventually we realise the entities referred to in this diagram are the Spider-Man movies. This gives us B = SPIDER-MAN, J = AMAZING, D = HOME.

Since B also appears in the diagram labelled Matchup, we can be confident that this entire puzzle is about the Marvel Cinematic Universe. The format of this diagram leads us to conclude that these are the two opposing sides featured in Captain America: Civil War. We can then deduce that the leaders of the two factions are A = CAPTAIN AMERICA and K = IRON MAN.

Through further deductions we can conclude that the Leaderboard diagram refers to possession of the Infinity stones at various points, the Table diagram refers to Phase 4 shows available on Disney+, and the diagram labelled "................ ()" corresponds to characters in mid/post-credits scenes.

This is the complete list of rules that can be deduced:

• Grey cells in tables refer to movies or TV shows.
• Black cells in tables refer to characters.
• Superhero names are used instead of civilian names.
• Lists in Table and Matchup are ordered alphabetically.
• Colored backgrounds behind tables indicate which phase the movie being referred to is in.
• Movies are listed in chronological (and therefore Phase) order.
• Words that are not referenced by a letter (A through P) are replaced by ellipses everywhere.
• All possible instances of the letters A through P are referenced. That means that ellipses never represent these entities.

Indexing into the extracted words/phrases in order gives us the final clue phrase CROESUS DEMONYM, which resolves to the final answer LYDIAN.

Authors' Notes

I really enjoy solving "Australian-style" puzzles because making a breakthrough in one gives you a unique rush of dopamine and makes you feel very smart. Hopefully teams that solved this puzzle experienced something similar!

Appendix

Matchup

Table

Captain Marvel appears in the post-credits scene of Ms. Marvel, which allows us to disambiguate the only show in this series that does not contain a reference to a previous MCU character (phew!).

............... ()

Captain America

In the post-credits scenes of Captain America: The First Avenger and Ant-Man, Captain America is shown talking. In Spider-Man: Homecoming, he breaks the fourth wall and talks to the audience directly.

Collector

In the mid-credits scene of Thor: The Dark World, Collector is shown talking. In Guardians of the Galaxy, his face is licked by the good girl Cosmo.

Nick Fury

In the post-credits scenes of Iron Man, Thor and Captain America: The First Avenger, Nick Fury is shown talking. In Iron Man 2, he is not pictured (and does not talk either). In Avengers: Infinity War, he disintegrates as a result of the snap. In Spider-Man: Far From Home, he is revealed to be Talos in disguise.

Leaderboard

One might argue that the Asgardians possessed 2 infinity stones at once, but this is never directly pictured in the movies. Additionally, it seems reasonable that the leaderboard only applies to individual characters, and the Tesseract that was stored in Odin's Vault isn't necessarily owned by any single Asgardian.

The Reality Stone was only given to the Collector at the end of Thor: The Dark World, so he does not appear in the left half of the leaderboard (whose transition occurs in Phase 1).

SPIDER-MAN

In an earlier version of the puzzle, the numbers 2 and 3 were replaced by ellipses. This made the break-in too hard for testsolvers, so the change was reverted.