Christmas Collection Event (BTD6)

The Christmas Collection Event was an event in Bloons TD 6 first introduced on 20th December 2019, several days after Version 14.0. The player received presents for every finished map, together with ordinary rewards such as Monkey Money or medals. The number of presents was based on game and track difficulty. After collecting a certain amount of presents, the player was rewarded with a crate. After opening the crate, the player received two (or three in later stages) Insta-Monkeys. As the player collected more presents, the crates increased in quality, requiring more presents to open but yielding higher quality Insta-Monkeys in turn.

In 2019, the Christmas Collection Event lasted 13 days (?), from December 19th/20th to January 1st/2nd.

In 2020, the Christmas Collection Event lasted 23 days, from December 13th/14th to January 5th/6th.

In 2021, the Christmas Collection Event lasted 23 days, from December 10th/11th to January 3rd/4th.

Present rewards (2019-2020)
Present rewards for finishing a map were following:

Crate rewards (2019-2020)
Each new tier of crate was unlocked depending on the number of presents collected:
 * Wooden Crate (Tier-1) - Default
 * Bronze Crate (Tier-2) - 100
 * Silver Crate (Tier-3) - 250
 * Golden Crate (Tier-4) - 450
 * Diamond Crate (Tier-5) - 1000

Each type of crate required a specific amount of presents before being allowed to collect the crate's special Instamonkey rewards:
 * Wooden Crate (Tier-1) - 20
 * Bronze Crate (Tier-2) - 30
 * Silver Crate (Tier-3) - 40
 * Golden Crate (Tier-4) - 50
 * Diamond Crate (Tier-5) - 70

Each type of crate rewarded the following Instamonkeys:
 * Wooden Crate (Tier-1) - 2 Instamonkeys, Tier-1 (high chance) and Tier-2 (low chance)
 * Bronze Crate (Tier-2) - 2 Instamonkeys, Tier-1 (low chance), Tier-2 (high chance) and Tier-3 (low chance)
 * Silver Crate (Tier-3) - 2 Instamonkeys, Tier-2 (high chance) and Tier-3 (low chance)
 * Golden Crate (Tier-4) - 2 or 3 Instamonkeys, Tier-3 (high chance) and Tier-4 (low chance)
 * Diamond Crate (Tier-5) - 2 or 3 Instamonkeys, Tier-3 (medium chance), Tier-4 (high chance) and Tier-5 (low chance)

Trivia

 * There was only one event change compared to the 2019 Halloween Collection Event: the chance for Tier 5 towers from Diamond Crates is decreased by a fair amount.
 * In the 2019 event, the best methods of farming include Dark Castle Easy (for quick AFK), Workshop Easy (super fast completions), and Dark Castle Impoppable (most efficient per unit time for farming Instas).