Unlock Juice

Unlock Juice, sometimes called simply JUICE, is a visible tracker of progress within a puzzle hunt, as well as a way to determine when milestones that determine new unlocks have been hit. While many hunts may use hidden point values assigned to puzzles to determine when teams have solved enough to unlock new content, hunts that use Unlock Juice will have that number visible to solvers, allowing to be used as both a morale booster and a gauge for how close the next unlock may be.

Unlock Juice is an alternative to other traditional unlock structures such as adjacency unlocks or timed unlocks. Additionally, Unlock Juice refers specifically to currencies and metrics that allow new rounds and puzzles to be unlocked. Similar systems that allow the purchase of hints or free solves will be found under Hint Currency.

Etymology
The word 'Juice' in this element's title comes from the 2021 MIT Mystery Hunt, in which teams had to accrue enough 'interdimensional energy' to unlock new areas of campus within the hunt's Projection Device. According to the introduction to the Projection Device, no appropriate unit existed yet, so the programmer (J. Linden) has to come up with their own term. Taking inspiration from their own first initial, they called it JUICE.

Rise in Popularity
Unlock Juice was not used very often in puzzle hunts until the 2010s. While individual hunts' decisions to use their particular unlock structure is unknown, hunts that didn't use elaborate websites tended to use simpler unlock mechanisms (sometimes to reduce stress on the running team having to manually update the site, and sometimes for the sake of less pre-hunt work on the site). As an example, the first MIT Mystery Hunt that used a form of Unlock Juice only applied the unlocks to the puzzles that were part of the hunt's endgame. This reduced the amount of interaction the average puzzle had with this system, and allowed for an otherwise entirely linear unlock system.

As hunts have grown more prolific over the years, unique unlock structures and themed hunts have become more common. In addition, websites have increased in quality by quite a bit (especially with the advent of gph-site). This has allowed hunt-runners to experiment with their unlock systems more, which has resulted in many more hunts choosing to use a thematic Unlock Juice.

Notable Examples

 * MIT Mystery Hunt 2007 - Had 8 different meters that counted a few different things. 7 of the meters were tied to a particular deadly sin, and would be filled when one of the 7 puzzles marked with that sin's image was solved. One bigger meter was filled whenever one of the 9 (non-intro) metas was completed, as well as whenever one of the 7 Sin Puzzles was solved. It wasn't Unlock Juice as we know it today, but it was the first unlock structure of its kind used in the MIT Mystery Hunt.
 * MIT Mystery Hunt 2009 - Solving puzzles gave teams different amount of 'dollarbucks', a currency that not only indicated how far into the hunt a team was, but could actually be spent at an in-hunt store. Spending dollarbucks allowed teams to upgrade their ship and fly further, essentially letting them choose what rounds to unlock based on the amount of money they had.
 * Galactic Puzzle Hunt 2018 - As teams gained cookies they unlocked new puzzles. While solving puzzles was one way to get large numbers of cookies at once, solvers could also click one of the giant cookies on the main hunt page, gaining one cookie per click. Unlocking puzzles only by clicking quickly became near impossible, but the hunt was unique in having a non-solving way to generating more Unlock Juice.
 * MIT Mystery Hunt 2020 - The hunt began by having teams fix attractions by solving puzzles, generating 'Buzz' about Penny Park in the process. However, once the second half of the hunt was unlocked and teams had access to more 'experimental' attractions, 'Buzz' stopped being generated. Instead, solvers would generate 'Wonder'. Wonder and Buzz were effectively identical, but it was the first time a hunt changed the name of its Unlock Juice midway through the hunt.