I was thinking that this could be a background for the July event. Like many stars falling out of the sky at once, or the whole sky sparkling with stardust (I know that there is a decor for it, but this would be different).

If possible, maybe have this option only for players who have sacrificed lions/lionesses the previous year? If not then just have it as regular reward for sacrificing a specific amount of lions/lionesses?

Flavor text.

You lead [NAME] to the Stone. [NAME] touches it, curious about the radiance, and vapors immediately into something that Apedemak calls stardust. "Don't worry," he says. "They will return next year as Meteorite Shards, falling from the sky when I call them!" Unsure about the fate of the lion that the Stone just killed, you accept the reward that Apedemak offers you: _.
30% Energy
30 SB
3% IMP
EXP (Level x 20)
Heartfelt Homecoming

If you accept Heartfelt Homecoming, this could be the Flavor text:
You realize that the there is something... familiar about the reward you have chosen, but you can't place your paw on it. It's as if... some long lost family and friends have finally come home.

Possible Heartfelt Homecoming text in Hoard;
The falling stars create stardust that float in the air, watching over you with a familiar warmth.