For our entire lives, we have celebrated Yargle Day every single September 3rd. This is well-known information and taught over and over again in schools, but here are a few Yargle Day reminders:

If you hear footsteps on your roof, REMAIN CALM. Yargle can smell your fear.
It doesn't matter if you're naughty or nice, Yargle's gaping maw is large enough to accommodate both kinds of children at once.
Save your milk and cookies for December. Consider tying a goat to a fence on the outskirts of your property, and maybe he'll get full.
Yargle never gets full.

It seems a single card in Dominaria was not enough to appease this beautiful, cruel spirit, so we have printed several popular cards with new art celebrating his glorious visage. We fondly remember the sacrifices artists who undertook this daunting challenge: Dmitry Burmak, Jehan Choo, Matt Dixon, Chuck Lukacs, and Franz Vohwinkel. May Yargle have mercy on their souls.