This achievement is for completing 25 challenges across "War Games", "Spartan Ops", and "Campaign". In the start menu next to your service record there is a tab labeled challenges. In that you can view the current challenges for each game type.
There are:
Daily
Weekly
Monthly
These challenges will require you to do something specific in each game mode such as for War Games getting 9 kills with a secondary weapon in one game. You can track your progress of a challenge in the same place you found it. Challenges are not to be confused with commendations, they are an entirely different thing. Once you have reached 25 challenges completed your achievement "should" pop.
Additional Notes: Challenges can not be repeated.
The number of challenges completed can be viewed in your service record menu in game under Spartan - War Games tab.
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Updated 9/15/2019***
From commentor: lightsup55I just wanted to add a little more (especially when challenges reset)...
It is impossible to get 25 challenges done in 1 day (or even 1 week for that matter).
There is a total of 6 weekly challenges, 2 daily challenges, and 1 monthly challenge.
You can find some (old)
examples of challenges at the
Halo Alpha wiki on Fandom.com.
Campaign Weekly: 2 challenges
- Both challenges typically require you to complete a (full) mission on Heroic (or Legendary) difficulty with specific skulls turned on.
Must start at Rally Point - Alpha. They can be completed solo or co-op. Both challenges must be completed before
Monday at 10:00 AM UTC (click the link to convert time to your area).
War Games Daily: 2 challenges
- Both challenges typically require you to get a certain number of kills with a specific weapon or weapon type. One or both may require you to do this in a single match. Both challenges must be completed before
tomorrow at 10:00 AM UTC (click the link to convert time to your area).
War Games Weekly: 2 challenges
- Both challenges typically require you to win a set number of matches of a specific game type. Both challenges must be completed before
Monday at 10:00 AM UTC (click the link to convert time to your area).
War Games Monthly: 1 challenge
- This challenge typically requires you to win a set number of War Games matches for the month. Both challenges must be completed before
the 1st day of next month at 10:00 AM UTC (click the link to convert time to your area).
Spartan Ops Weekly: 2 challenges
- Both challenges typically require you to kill a set number of enemies of a specific type. They can be completed in any Spartan Op chapter of any episode on any difficulty (including Easy) that has that specific enemy type. If the challenge requires you to kill Hunters, note that they usually appear in groups of 2 and only on specific Spartan Ops chapters (usually later in the chapter after certain objectives are completed). Both challenges must be completed before
Monday at 10:00 AM UTC (click the link to convert time to your area).
Waypoint: 0 challenges
-
No Waypoint challenges are currently available. (this is always the case)
- The
Halo Waypoint app can be downloaded from the Xbox 360 Store and requires an Xbox 360 console to use. This app doesn't always work and sometimes gives an error saying that the Waypoint servers aren't available. Just keep trying or try again about 1 hour later.
- Alternatively, you can use
HaloWaypoint.com, click GAMES,
Halo 4, then click
STATS APP to view your Halo 4 stats (including the currently running challenges and your progress towards them). You will need to log in with your Microsoft/Xbox account to view these stats.
Past Updates:Update: 5/4/2016As of May 1st, Halo 4 challenges are back online. Get to work on the challenges as soon as you can in case issues mentioned below every happen again.
Update: 2/21/2016Since 1/1/16 this achievement may now be unobtainable. Challenges have ceased to be updated and there has been no response from 343i on the matter.
If you'd like to way in on the issue there is a petition via Change.org created by, TA user "Seitzz", for the issue. Alternatively, you can continue tweeting/DM @Brav on twitter who is the community manager for 343 and generate enough interest for them to get to fixing the issue.
https://www.change.org/p/halo-bring-back-halo-4-challenges?r...Update: 1/6/2016In the past few months, there have been a few instances where challenges have been non-existent on Halo 4. Most recently since the new year has begun players have been without challenges. For any and all future issues I suggest posting your issues on the Halo Waypoint forums at the following link for Halo 4 support. I cannot provide anything other than what I have provided here to resolve your issues. There is no fix if challenges aren't there, they are a part of the Halo 4 servers and if 343 chooses not to put them out there then you're out of luck.
https://www.halowaypoint.com/en-us/forums/36cecc379ca14abd91...Updated 11/12/12: Some users report that the achievement wouldn't unlock till more than 25 challenges were completed. No definite explanation but the common symptoms include not completing the game mode in which the challenge was completed in. i.e. playing a chapter of spartan ops and earning the challenge mid-way and then quitting out. May also be due to the server issues that were plaguing the launch of Halo 4.