List of curated daily challenges

Date	Event, if any	Peculiarities
January 1st	New Years	Bomb pool, starting with Pyro, no tears
January 14th		Starting as Guppy, no item rooms
January 16th	National Nothing Day	No item rooms, no shops
January 27th		No item rooms, no shops, Poop pool
February 2nd	Groundhog day	Same seed as the day before
February 9th	National Toothache Day	51 luck, Tooth items, no item rooms
February 11th	National "Don't Cry Over Spilled Milk" Day	Starting with Soy Milk and Milk!
February 14th	Valentine's day	High luck, Mom's items
February 18th	National Battery Day	Starting with battery-related items
March 2nd	Edmund's birthday	Isaac to Mega Satan, Undroppable The Left Hand
March 4th	Holy Experiment Day	Maggie to Mom. No Item Rooms, starting with Immaculate Conception, Eucharist and Seraphim
March 17th	St. Patrick's day	Cain to Mega Satan via The Chest, starts with high luck
March 20th		Isaac, starts with Cone Head, The Parasite and Tractor Beam
Easter	Easter	Lazarus, Blood Of The Martyr, Stigmata, no item rooms
April 1st	April fools	Old Keeper, random trinkets and items upon pickups
May 8th	Mothers' day	Isaac, Mom transformation, no item rooms
May 30th	Memorial day	The Lost, no tears, 3 familiars and Conjoined
June 19th	Fathers' day	Cain, Daddy Longlegs, Dad's Key
June 25th	Pride day	The Lost, rainbow items
July 4th	Independence day	Samson, Dr. Fetus, bomb pool
October 31st	Halloween	Eve, Sack Head
November 1st	Day of the dead	The Lost w/o Holy Mantle, Dead Cat
November 11th	Veterans' day	The Lost, no item rooms
November XXth	Thanksgiving	Cupid's Arrow, Rotten Meat
December 5th
December 6th	Satoru Iwata's birthday	Iwata's sprite, The Gamekid
December 25th	Christmas	A Quarter, A Lump of Coal, Xmas hat

The full list of the remaining undisclosed dailies isn't published to avoid spoiling content.