Recently Revealed Dossiers
480 creatures are announced, 475 of them released and 5 yet to be released.
Official Tweets
Current Events
The following Events are currently active or have been announced.
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Extinction has concluded and Extinction was released.
The 
Extinction Chronicles is a series of routinely drops adding new Explorer Notes, Tek-themed Creatures, and Skins related to the upcoming DLC Extinction.
It runs until November 6th, 2018.
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ARK: Evolution Event has been concluded. This Evolution Event includes:
2x Harvesting Rates
2x Taming Rates
2x EXP Rates
NOTE: This Event only affects official servers that don't have already boosted rates.