A device used to decode a Coded Box. When used, a random weapon in both the Top 50 and Top 30 list can be obtained for permanent or with a period of 7, 30 or 100 days. 15 Mileage Points will be awarded upon use.
- South Korea: 29 December 2016.
- Taiwan/Hong Kong: 3 January 2017
- China: 4 January 2017
- Japan: 18 January 2017
- Indonesia/CSN:Z: 8 February 2017
These weapons are the "special guests" that only appeared during their first release and removed two weeks afterward. The weapons return after 6 months of its initial release and available permanently afterwards except for Red Dragon Cannon which is only available for 2 weeks, later re-added 1.5 years after initial release. The weapons are also added to Mileage Auction.
- Top 50 Decoder
- South Korea
- 29 December 2016: Firstly introduced.
- 19 January 2017: Added Red Dragon Cannon, Special Duck Foot Gun, Sterling Bayonet (3 weeks)
- 2 March 2017: Added Brick Piece S1451 (3 weeks)
- 20 April 2017: Added Python Desperado (Premium, 1 month)
- 1 June 2017: Added Bunker Buster LTD (1 month)
- 29 June 2017: Added AUG Guardian (Premium, 1 month)
- 27 July 2017: Readded Red Dragon Cannon (2 weeks)
- 10 August 2017: Added Pesticide Sprayer (1 month)
- 16 August 2017: Rearrange the contents (Replaced Lightning AR-1 and Crossbow with Special Duck Foot Gun and Sterling Bayonet)
- 7 September 2017: Added Bouncer (1 month)
- 21 September 2017: Added Dual Sword Phantom Slayer (Premium, readded Python Desperado, 1 month)
- 19 October 2017: Added Stun Rifle (1 month, replaced Brick Piece M777 with Brick Piece S1451)
- 16 November 2017: Added Star Chaser SR (1 month)
- 18 January 2018: Added Magnum Lancer (2 months)
- 8 March 2018: Added Arm Torch (1 month, replaced SKULL-9 with Bunker Buster LTD)
- 22 March 2018: Added Claymore Mine MDS (1 month)
- 19 April 2018: Added Dual Beretta Gunslinger (Premium, readded Dual Sword Phantom Slayer, 1 month)
- 3 May 2018: Rearrange contents (Replaced Crowbar Maverick, VULCANUS-9, and FG-Launcher with Red Dragon Cannon, Bouncer, and Pesticide Sprayer)
- 23 August 2018: Rearrange contents (Star Chaser SR is added to Top7, Bouncer is descended to Top25 and M950 to Top50 while THANATOS-7 is removed.)
- 13 September 2018: Added back Python Desperado to Top 50 Decoder and held two fold probability event.
- 20 September 2018: Added Python Desperado to Top 7, descended SG552 Lycanthrope to Top 25 and Black Dragon Cannon to Top 50.
- 1 November 2018: Added Stun Rifle and Arm Torch to Top 7, descended Blood Dripper and Gáe Bolg to Top 25, Savery and Volcano to Top 50, and removed THANATOS-5 and BALROG-XI.