If they do this, then there needs to be an episode where one of the characters goes:
“Hey, wait, what day is this?”
“It’s Tuesday.”
“Tuesday! It’s time, come with me.”
After traveling for 20m of the episode where assorted shenanigans ensue, they arrive at an old tomb. Pushing the door open, they enter the room and find a large, shining chest.
“This is a magical chest, it seems to regain its power every seven days.”
You can tell by the expression of the character how excited they are, excited for discovering the chest, excited to see the magic has returned, excited in anticipation of what’s inside.
After messing with the lock, cursing out loud about “stupid puzzles”, the chest pops open. As it does, the shine and light on it dims.
The character reaches inside, eyes glinting, and finds a beautiful sword. Showing the finest craftsmanship, jewels on the hilt.
He draws it out, raising it, trying to catch the light of the dimming sun through the door of the tomb. Then, he pulls out his own sword.
They’re the same. Identical in every way. In disgust he throws it on the ground, and storms out of the tomb.
Roll credits.