Each day you get the number of the day as slots. For example 5th December 5 slots, 23th December 23 slots.
So a LOT of nice little gifts are waiting for you.
The final reward are 100 Auto Miner Cores and 1 Alien Core to keep your structure warm until next year
Just activate the X-mas PDA mission and head to ECC to the Advent Ring.
If you’re not online on Dec 24th (i.e. at the fam’s house) are you able to get that day’s prize later? When is the wreath getting deleted I guess would be a better question?
Nope, like a real advent calendar you can do all 1-24 doors even on 24th december one by one afterwards. And the event will be available until the full wipe in case people are away by their families or so.
Merry R E X M A S 
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