Daily Challenge Vault

 is an update that was released for Bloons TD 5 on the 2nd of May, 2012. It allows players to replay previously incomplete Daily Challenges for a lower reward (40%) or previously completed for 16% (40% of 40%) reward. If players play challenges from the vault, players will play them mostly with rules of the actual patch (For example: If players play a challenge from Feb 7, 2012, players can use towers and agents like Spike Factory or Bloonsday Device that were released after the date of the challenge) with a few exceptions (like Feb 28, 2012 where Bloonsday Device and Tribal Turtle are not available).

Players can play daily challenges from 27th January 2012 - 30th June 2018. When the player completes a month of Daily Challenges, they will get a Medal and 40.

Trivia

 * The vault for January 2012 only has five Daily Challenges. Beating all of them counts as a month and will award the achievement.
 * March 11th's, April 8th's, July 30th's, and August 8th's Daily Challenge give you 2 upon completion, while February 7th's Daily Challenge gives out 8. This is because the challenges are very short.