The first pictures of two of the five cards in the Promotion Pack 2023, awarded at the JUMP Festa 2023, have been revealed. In order to obtain this pack, you can take part in the various events at the JUMP Festa. The website says that they are considering re-distributing the pack in future events.

綱引犬会 Tsunahiki Inukai
[…] Spell Card

Much like the art depicts, “Tsunahiki” (綱引) is a game of tug of war, and the latter part seems to be a pun on “tournament” (大会) having its first kanji replaced by the similar-looking “dog” (犬), to feature the sumo wrestler Yokotuner (which also includes “rope” in its name).

The name is mostly composed of this large number, which seems to be related to 24-bit true color depth. By combining 256 variations of each of the three RGB colors, you get over 16,770,000 possible colors (256^3 = 16,777,216).

Sources: JUMP Festa 2023 website, Twitter post #1, #2.