It's the month of harvest, heralding in All Hallow's Eve! While in the US it usually results in orange and black (and occasionally white) dominating most households, as well the wee ones rampaging the streets for sweets (while the older and not-so-mature ones pulling pranks), there's more to the origins of Halloween from long before in Ireland. And then there are events that deal with the dead that doesn't necessarily fall during autumn. For example, Mexico has Day of the Dead on November 1 and 2; China with the Spirit Festival (or Ghost Festival) on the 14th night/15th day of the 7th lunar month (September 3 on this year's Gregorian calendar), and Japan has the Obon festival starting July 15 or August 15 depending on region (coincidentally, the old Obon date was the same as China's date of the 15th day on the 7th lunar month before Japan switched to the Gregorian calendar).
Your challenge: Instead of just Halloween, give us scenarios or situations that the canon Transformers would definitely find scary or horror from their perspective, close encounters with those not of the physical plane, or experiencing humans performing ancestor worship. Maybe the Boneyard in Tucson, Arizona, for those with jet and helicopter modes. Someone attending the Obon festival and their thoughts of Gozan no Okuribi in Kyoto. Heck, a marathon of all those horror movies, from the original "Friday the 13th" to "Nightmare on Elm Street" to "Ju-on" and "Ringu" (and we mean the original Japanese versions)!
Start scaring those pants - and manifolds - off! And do keep it family friendly!