This achievement has been updated. It is now for completing 10 of the weekly challenges
that have been in the game. The previous challenges have now been added back into the game through an update.
Completing 10 of these will unlock the achievement. From VOODOO85, you can access the challenges from this location:
You can find these under 'Activities > Landing Challenges > Famous/Epic etc' and are labelled as Spotlight Events. I've had another gamer confirm that their progress went from 40% to 70% so if they complete another 3 events from the pack, they'll pop the achievement too
It's also worth noting that this update is only available through the Xbox Insider program at this point in time.
Previously, this achievement would have taken years to complete and may have become impossible for some users. Nevertheless, it doesn't even take ten weeks now, and can be done in a matter of minutes.
Congrats to all who have waited years for this update!
Outdated guide:
*** Spoiler - click to reveal ***Edit: New, more permanent guide established.
Warning: Unless something is changed, there is a possibility that you will never be able to unlock the achievement. They seem to not be releasing challenges more than once every several months, and the new game is about to come out, meaning this might not be supported for long. Tread carefully.
Important:
As HiddenJaguar25 points out, and further confirmed by others, if you complete the same exact event on Windows and on Xbox Series X|S (Or xCloud), you can get two advancements towards the achievement (20%).
xCloud counts as Xbox Series X|S. You cannot get 30%. However, if you only have a PC, you sometimes will not need an Xbox Series X|S because you can do it through xCloud. (With the exception of when they have update previews. You'll have to wait for it to officially be released.)
That means supposedly every single time a new event comes out, you can get 20% on the achievement. Making it so that you need only five 'Different' events.
This does not, however, work when you do it multiple times on the same platform. (2 PC's or 2 Xboxes)
To earn the "Decathlon" achievement, you must complete 10 SPOTLIGHT events! The weekly activities is a false description, and they're most certainly not weekly. They very rarely come out with a new one when they have a major update, which is every couple months, but lately they have not been adding them much at all. This means that this achievement, at this rate, will likely take 2+ real-life years, if the game is supported for that long. (for 10 'events'). There's no date changing as they're tied to the sever. The old one is inaccessible and removed once they add a new one.
The spotlight challenges will be on the main menu as soon as you start the game. In the upper left-hand corner.
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CURRENT EVENT:
Right now, as of January 2024, First Flight Airport is still the only challenge available. We have not gotten a new one in a very long time.
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Post completion update:
I started this game on July 22nd, 2021 at 5:38 pm. It is now July 9th, 2022 and I just completed the game at 9:13 pm today. It was quite the journey that I stuck with through many important events in my life. It is certainly the longest time I've ever spent to complete one game, (Let alone a single achievement) This will be a game that I will never forget.
Video of achievement pop:
Please comment on this solution when a new one comes out, and I'll add to it what the current spotlight challenge is. You can also check this thread, where people usually post when a new spotlight event is out.
Spotlight Events
Old guide:
*** Spoiler - click to reveal ***Warning: This achievement will likely take around 1 year to complete.
Important:
As HiddenJaguar25 points out, and further confirmed by others, if you complete the same exact event on Windows and on Xbox Series X|S (Or xCloud), you can get two advancements towards the achievement (20%).
xCloud counts as Xbox Series X|S. You cannot get 30%. However, if you only have a PC, you sometimes will not need an Xbox Series X|S because you can do it through xCloud. (With the exception of when they have update previews. You'll have to wait for it to officially be released.)
That means supposedly every single time a new event comes out, you can get 20% on the achievement. Making it so that you need only five 'Different' events.
This does not, however, work when you do it multiple times on the same platform. (2 PC's or 2 Xboxes)
To earn the "Decathlon" achievement, you must complete 10 SPOTLIGHT events! The weekly activities is a false description, and they're most certainly not weekly. They sometimes come out with a new one when they have a major update, which is about once a month, but lately they have been adding them every two or three world updates. This means that this achievement will likely take around 1 year. (for 10 'events'). There's no date changing as they're tied to the sever. The old one is inaccessible and removed once they add a new one.
The spotlight challenges will be on the main menu as soon as you start the game. In the upper left-hand corner.
I added a picture for those who cannot find it.
https://imgur.com/a/SWsHsTM
However, several people are having trouble getting these to show up. (Discovery flights appear instead of the Spotlight Challenge.) If you're in the same position, thankfully, Spoof Ex has found a solution to this:
*** Spoiler - click to reveal ***"To get the Spotlight Challenge to show up if it isn't you need to do the following:
1. Start Naples Discovery Flight
2. Hit Active Pause (Pause on the Keyboard no idea on XB)
3. Let it run like this for 4 hours
4. Quit.
5. Restart Game.
The Spotlight will now appear. It seems it is tied exclusively to the Discovery Flights timers."
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CURRENT EVENT:
Right now, as of 9/21/2023, First Flight Airport is still the only challenge available. We have not gotten a new one in 5 months.
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Since the Xbox release, you should have been able to obtain 100% progress on this achievement, as long as you took advantage of every possible opportunity.
Breakdown:
*** Spoiler - click to reveal *** Miramar: (Xbox Series X|S) (November 18th, 2021) [+10%] (Removed on January 31st, 2022)
Miramar: (PC) (November 18th, 2021) [+10%] (Removed on January 31st, 2022)
RENO STEAD: (PC) (February 12th, 2022) [+10%] (Removed on February 18th, 2022)
RENO STEAD: (PC) (February 18th, 2022) [+10%] (Removed on March 25th, 2022)
RENO STEAD: (Xbox Series X|S or xCloud) (March 2nd, 2022) [+10%] (Removed on March 25th, 2022) (Glitchy)
Kingston Nevada: (PC) (April 1st, 2022) (Removed on April 21st, 2022) [+10%]
Kingston Nevada: (Xbox Series X|S) (April 1st, 2022) (Removed on May 23rd, 2022) [+10%]
Kingston Nevada: (PC) (April 22nd, 2022) (Removed on May 23rd, 2022) [+10%]
Entebbe Uganda: (Xbox Series X|S) (July 8th, 2022) [+10%]
Entebbe Uganda: (PC) (July 8th, 2022) [+10%]
=100%
If you've caught ALL of the possible advancements since the Xbox release, you will have received the achievement! Hooray! 
Post completion update:
I started this game on July 22nd, 2021 at 5:38 pm. It is now July 9th, 2022 and I just completed the game at 9:13 pm today. It was quite the journey that I stuck with through many important events in my life. It is certainly the longest time I've ever spent to complete one game, (Let alone a single achievement) This will be a game that I will never forget.
Video of achievement pop:
Please comment on this solution when a new one comes out, and I'll add to it what the current spotlight challenge is. You can also check this thread, where people usually post when a new spotlight event is out.
Spotlight Events