How do I start event on single player?

[Tanya]

There is a new option to add an event when loading in. What do I put in the text box?

[Stephen]

https://ark.gamepedia.com/Server_Configuration
eventname -> Description
Easter -> Allows for the Easter Event to be activated
Arkaeology -> Allows for the Arkaeology Event to be activated.
ExtinctionChronicles -> Allows for the Extinction Chronicles Event to be activated.
WinterWonderland -> Allows for Winter Wonderland 2020 Event to be activated.
vday -> Allows for Love Evolved to be activated.
Summer -> Allows for Summer Bash 2020 Event to be activated.
FearEvolved -> Allows for ARK: Fear Evolved 4 to be activated.
TurkeyTrial -> Allows for ARK: Turkey Trial 4 to be activated.
birthday -> Allows for ARK: 5th Anniversary to be activated.
None -> Disables active event.
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dev tends to removed event assets once the event is ended, so some event items are missing even if you start it manually, for instance the xmas tree from winter wonderland. What you can still do is having wild dino spawn in event color, other than that I don't really think activating event by yourself outside the event time window is useful.