Halloween

Halloween is an Earth holiday in which humans dress up in strange outfits that make them look like other people or things. It is usually celebrated on October 31, and is a ritual to celebrate the end of Summer which started in Ireland many centuries ago, though it has evolved significantly since then.

Transformers: Rescue Bots
Due to Griffin Rock's cold climate in late October, the residents instead celebrated "Earliween", a Halloween analogue that took place during warmer months so that the children could freely show off their costumes. One particular Earliween ended with all of Griffin Rock filming an alien invasion hoax video in order to maintain the Rescue Bots' secrecy from the rest of the world.