Christmas Season is a seasonal event in Cookie Clicker that was added on the 1.04 update. The event was active during versions 1.04 - 1.0403 without a way to turn it off. Since version 1.0466, Christmas season starts automatically and lasts from the 15th to the 31st of December. Since the introduction of the Season switcher in version 1.041, Christmas Season can also be activated by purchasing the Festive biscuit, which will launch it for 24 hours. Like all season switcher upgrades, it is repeatable, but will get more expensive every time you buy it, like buildingss, and will also cancel any other seasonal event that is active at this time.
Christmas season brings two major features, reindeer and Santa. Reindeer will occasionally appear and hop across the screen. Clicking them will give 1 minute's worth of cookies and has a chance to unlock one of the Christmas-themed flavored cookie upgrades (see below). Santa is a widget that appears in the bottom-left corner of the screen after purchasing the first upgrade available during the season, A festive hat. Upgrading Santa will unlock specific upgrades which provide various effects.
Aesthetic changes include snowflakes alongside the falling cookies, wrinklers having red and white stripes on their bodies and Santa hats on their heads, and elf grandmas appearing alongside the other grandmas.
These Upgrades can be unlocked by upgrading Santa.
| Icon | Name | Unlock condition | Base price | Description | ID |
|---|---|---|---|---|---|
| A festive hat | 25 cookies baked during Christmas season | 25 | Unlocks. something. "Not a creature was stirring, not even a mouse." | 152 | |
| Increased merriness | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Cookie production multiplier +15%. Cost scales with Santa level. "It turns out that the key to increased merriness, strangely enough, happens to be a good campfire and some s'mores. You know what they say, after all; the s'more, the merrier." | 153 | |
| Improved jolliness | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Cookie production multiplier +15%. Cost scales with Santa level. "A nice wobbly belly goes a long way. You jolly?" | 154 | |
| A lump of coal | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Cookie production multiplier +1%. Cost scales with Santa level. "Some of the world's worst stocking stuffing. I guess you could try starting your own little industrial revolution, or something. " | 155 | |
| An itchy sweater | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Cookie production multiplier +1%. Cost scales with Santa level. "You don't know what's worse : the embarrassingly quaint "elf on reindeer" motif, or the fact that wearing it makes you feel like you're wrapped in a dead sasquatch. | 156 | |
| Reindeer baking grounds | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Reindeer appear twice as frequently. "Male reindeer are from Mars; female reindeer are from venison." | 157 | |
| Weighted sleighs | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Reindeer are twice as slow. Cost scales with Santa level. "Hope it was worth the weight. (Something something forced into cervidude)" | 158 | |
| Ho ho ho-flavored frosting | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Reindeer give twice as much. Cost scales with Santa level. "It's time to up the antler." | 159 | |
| Season savings | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | All buildings are 1% cheaper. Cost scales with Santa level. "By Santa's beard, what savings! But who will save us?" | 160 | |
| Toy workshop | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | All upgrades are 5% cheaper. [note 1] Cost scales with Santa level. "Watch yours-elf around elvesdroppers who might steal our production secrets. Or elven worse!" | 161 | |
| Naughty list | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Grandmas are twice as productive. Cost scales with Santa level. "This list contains every unholy deed perpetuated by grandmakind. He won't be checking this one twice. Once. Once is enough." | 162 | |
| Santa's bottomless bag | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Random drops are 10% more common. Cost scales with Santa level. "This is one bottom you can't check out." | 163 | |
| Santa's helpers | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Clicking is 10% more powerful. Cost scales with Santa level. "Some choose to help hamburger; some choose to help you. To each their own, I guess." | 164 | |
| Santa's legacy | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Cookie production multiplier +3% per Santa's levels. Cost scales with Santa level. "In the north pole, you gotta get the elves first. Then when you get the elves, you start making the toys. Then when you get the toys. then you get the cookies." | 165 | |
| Santa's milk and cookies | Purchasing "A festive hat" or evolving Santa | 2,525 × 3 S | Milk is 5% more powerful. Cost scales with Santa level. "Part of Santa's dreadfully unbalanced diet." | 166 | |
| Santa's dominion | Reach the final stage of Santa | 2.525 quadrillion | Cookie production multiplier +20%. All buildings are 1% cheaper. All upgrades are 2% cheaper. [note 1] "My name is Claus, king of kings; Look on my toys, ye Mighty, and despair!" | 168 |
Owning all of these upgrades provides a total of:
Where S is the current level of Santa.
These 7 flavored cookie upgrades may drop from reindeer during the Christmas season.
| Icon | Name | Unlock condition | Base price | Description | ID |
|---|---|---|---|---|---|
| Christmas tree biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "Whose pine is it anyway?" | 143 | |
| Snowflake biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "Mass-produced to be unique in every way." | 144 | |
| Snowman biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "It's frosted. Doubly so." | 145 | |
| Holly biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "You don't smooch under these ones. That would be the mistletoe (which, botanically, is a smellier variant of the mistlefinger)." | 146 | |
| Candy cane biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "It's two treats in one! (Further inspection reveals the frosting does not actually taste like peppermint, but like mundane sugary frosting.)" | 147 | |
| Bell biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "What do these even have to do with christmas? Who cares, ring them in!" | 148 | |
| Present biscuits | Minimum 20% drop chance from finding a reindeer during Christmas season | 252.525 billion | Cookie production multiplier +2%. "The prequel to future biscuits. Watch out!" | 149 |
The current drop chance is 1-f, where f is the fail rate. The base fail rate is 0.8. There are several factors which can further reduce the fail rate.
| Modifier | Factor |
|---|---|
| Green yeast digestives | 1/1.03=0.970874 |
| Dragon teddy bear | 1/1.03=0.970874 |
| Santa's Bottomless Bag | 1/1.1=0.909091 |
| Let it snow | 0.75 |
| Starsnow | 0.95 |
| Selebrak, Spirit of Festivities | 0.9/0.95/0.97 (Diamond/Ruby/Jade) |
| Mind Over Matter, Reality Bending, both | 1/(1.25, 1.025, 1.275) = 0.8, 0.9756, 0.7843 |
| Cosmic Beginner's Luck | 0.2 |
| Garden plants (mature, dirt) | 1/(1+0.01G+0.01S+0.03K) |
G = # of Green Rot
S = # of Shimmerlily
K = # of Keenmoss
For example, if you clicked a reindeer with the Let it snow achievement and the Heavenly upgrade Starsnow, then the fail rate will be:
f = 0.8 ∗ 0.75 ∗ 0.95 = 0.57
If you clicked a reindeer with the Mind Over Matter aura active, and Selebrak in the diamond slot, the fail rate will be:
After figuring out the fail rate (f), calculate successful rate (s = 1-f) and use following table to find out the probabilities.
| Cookies Unlocked | Probability of Appearance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Formula | Base (s=0.2) | With Mind over matter (s=0.36) | With Santa's bottomless bag (s=0.272727) | All modifiers, No plants (s=0.929) | |||||||||
| 0 | s*7/7 | 20% | 1/5 | 36% | 1/2.8 | 27.3% | 1/3.7 | 92.9% | |||||
| 1 | s*6/7 | 17.1% | 1/5.8 | 30.8% | 1/3.2 | 23.3% | 1/4.3 | 79.6% | |||||
| 2 | s*5/7 | 14.3% | 1/7 | 25.7% | 1/3.9 | 19.5% | 1/5.1 | 66.4% | |||||
| 3 | s*4/7 | 11.4% | 1/8.8 | 20.6% | 1/4.9 | 15.6% | 1/6.4 | 53.1% | |||||
| 4 | s*3/7 | 8.57% | 1/12 | 15.4% | 1/6.5 | 11.7% | 1/8.6 | 39.8% | |||||
| 5 | s*2/7 | 5.71% | 1/18 | 10.3% | 1/9.7 | 7.79% | 1/13 | 26.5% | |||||
| 6 | s*1/7 | 2.86% | 1/35 | 5.14% | 1/19 | 3.90% | 1/26 | 13.3% | |||||
| Expected value for Reindeer clicked to unlock all | 363/20s | 91 | 50 | 67 | 20 | ||||||||
| Icon | Name | Description | ID |
|---|---|---|---|
| Coming to town | Reach Santa's 7th form. | 109 | |
| All hail Santa | Reach Santa's final form. | 110 | |
| Let it snow [note 2] | Unlock every Christmas-themed cookie. Owning this achievement makes Christmas-themed cookies drop more frequently in future playthroughs. | 111 | |
| Oh deer | Pop 1 reindeer. | 112 | |
| Sleigh of hand [note 3] | Pop 50 reindeer. | 113 | |
| Reindeer sleigher [note 3] | Pop 200 reindeer. | 114 | |
| Eldeer | Pop a reindeer during an elder frenzy. | 265 | |
| Baby it's old outside | Click one of Santa's helper grandmas during Christmas season. | 580 |