In Merge Dragons, events are time limited quests which have a theme and special rewards that you cannot get anywhere else. To unlock events, you must complete grassy 3 level and have 35 dragon power.
Rewards for events sometimes vary randomly as the game developers see fit.
How to win all items during a Merge Dragons event
This video guide by Dennis Michels shares some good information regrding events. For the most part, all events are the same technique. The items are just different.
Event Trick Harvesting
Check out this event trick harvesting video by Toasted Gamer Boutique. Toasted is an authority figure when it comes to anything Merge Dragons related! She is very helpful and quite a useful resource! She also live streams merge dragons events as they come out.
A historical reference for events that have already completed is below.
|Magic Moon Event (alt: Lunar Light Event, Fly Me To The Moon Event, Year's End Celebration Event*, Sakura Dream Event)||Moon||Moon Dragons, Blood Moon Plant (Second and Third Occurrences)||First Occurrence: 15th - 18th September 2017 (iOS) 6th - 9th October 2017 (Android) Second Occurrence: 25th - 28th May 2018 Third Occurrence (Lunar Light): 28th September - 1st October 2018 Fourth Occurrence (Year's End Celebration): 27th - 30th December 2018 Fifth Occurrence: 29th March - 1st April 2019 Sixth Occurrence (Sakura Dream): 19th - 21st January 2020|
|Halloween Event||Halloween||Ghastly Dragons, The Great Pumpkin, Haunted Mansion (Before 2.2.0)||First Occurrence: 27th - 30th October 2017 Second Occurrence: 26th - 29th October 2018 Third Occurrence: 25th 19:00 GMT - 28th 19:00 GMT October 2019|
|Thanksgiving Event||Thanksgiving Day||Thanksgiving Dragons||First Occurrence: 23rd - 28th November 2017 Second Occurrence: 9th - 11th November 2018|
|Ancient Games #1||Ancient Olympic Games||Stadium Dragons||13th - 18th December 2017|
|Christmas Event||Christmas||Winter Dragons, Winter Wonderland Snow Globe||First Occurrence: 22nd - 27th December 2017 Second Occurrence: 21st - 24th December 2018|
|Zen Dragon Event||Japan||Sensei Dragons, Temple (Second Occurrence)||First Occurrence: 19th - 24th January 2018 Second Occurrence: 17th - 20th August 2018 Third Occurrence: 11th - 14th January 2019|
|St. Valentine's Day Event||Valentine's Day||Passion Dragons, Entwined Passion Trees, Snuggles McCuddlesworth||First Occurrence:9th - 12th February 2018 Second Occurrence: 15th - 18th February 2019|
|Easter Event||Easter||Bunny Dragons, Super Bunn-Bunns||First Occurrence:30th March - 2nd April 2018 Second Occurrence: 12nd - 15th April 2019|
|Earth Day Event (alt: Ocean Breeze Event, Frozen Seas Event)||Earth Day, Ocean||Sea Dragons, Green Moon Starfish||First Occurrence: 20th - 22nd April 2018 Second Occurrence (Ocean Breeze): 31st August - 2nd September 2018 Third Occurrence (Frozen Seas): 26th - 28th January 2019|
|Toy Event (alt: Playing with the Past Event)||Toys||Doll Dragons, Rollerskate||First Occurrence: 11th-14th May 2018 Second Occurrence (Playing with the Past): 14th - 17th September 2018|
|Fairy Event (alt: Once Upon a Time Event)||Fairies||Morpho Dragons, Fairy Mushroom House||First Occurrence: 15th - 18th June 2018 Second Occurrence (Once Upon a Time): 12th - 15th October 2018 Third Occurrence (Shroomsand&Fairies) 26th - 29th April 2019|
|Summer Event (alt: Summer Dreaming Event*)||Summer||Diva Dragons, Camp Summer Shop (First Occurrence), Camp Ice Cream Shop (Second Occurrence)||First Occurrence: 29th June - 2nd July 2018 Second Occurrence: 3rd - 6th August 2018 Third Occurrence: 15th - 18th March 2019|
|Pet Event||Pets||Cat Dragons, Solid Climbing Toy, Bone Appetit||First Occurrence: 20th - 23rd July 2018 Second Occurrence: 16th - 19th November 2018 Third Occurrence: 7th - 10th June 2019 Fourth Occurrence: 8th - 10th November 2019|
|Chinese New Year Event (alt: The year of The Rat Event)||Chinese New Year||Turtle Dragons, Artful Bonsai Tree||First Occurrence:8th - 11th February 2019 Second Occurrence: 24th-27th January 2020|
|Carnival Event||Carnival of Brazil||Samba Dragons, Royal Feathered Mask||First Occurence:1st - 4th March 2019 Second Occurrence:21 - 24 February 2020|
|Owlympus Event||Greek Gods||Zeus Dragons, Golden Siren Statue||10th - 14th May 2019|
|Fire&Ice||Thanksgiving Day||Winter Dragons, Zeus Dragons||24th - 27h May 2019|
|Merge 5 Event||Merging||Varies||Zero Occurrence:22nd - 25th March 2019 (Beta) First Occurrence: 19th - 22nd April 2019 Second Occurrence: 17th - 20th May 2019 Third Occurrence: 31st May - 3rd June 2019 Fourth Occurrence: 14th - 17th June 2019 Fifth Occurrence: 28th June - 1st July 2019|
|Merge Combo Event||Merging||Varies||First Occurrence: 28th June - 1st July 2019|
|Camp and Chill Event **||Harvesting, building, "killing", merging||Varies||First Occurrence: 18th October - 21st October 2019|
|Best of 2019||Remembering the previous year||30 December 2019 - 2nd January 2020|