Returning player
Having the same problem with Red and Black Challenge
I cannot complete them and all free decks are Historic

Really wanted to play Standard again but got stuck by this problem

No matter what I do, it will not let me complete any of the 5th color challenges. I get the “Unable to join event” message for all 5 of them.

I just started playing again, but all my cards are obviously out of date. I can't finished any of these color challenges so I have 0 cards/decks rn to play with. Completely stuck. :(

Unless the bug has multiple versions I know the problem and the solution.
I am not sure why or how it happens but it's now clear to me that this bug happens due to the player not having the cards for the decklist, at some point throughout the challenge around 3 cards (meaning this keeps happening on one stage) will fail to be unlocked and added, this is why it seems inconsistent across the player base.

The solution is to simply craft those missing cards.
- Go to your deck screen (do not try this by navigating through the color challenge).
- click the decks you know aren't working, they will all have a yellow symbol overlayed on them.
- make sure to only 'select' the deck as we dont want to 'enter' the deck itself.
- now look at the bottom of the screen, there should be a wildcard symbol, you click that and you'll be able to craft all the missing cards. (for me it was consistently 3 cards).
- now your deck is "eligible" for PvP play and you may resume the challenge.

I came to this conclusion as it seemed some people had success with simply resetting the tutorial and replaying everything.
In case you do not have any wildcards to craft with, simply make a deck you can play with in normal PvP matches and just play a little for some quest rewards, it should not be that hard.

I hope this comment gets noticed as I believe this is a 100% fix without some bs technical workaround and maybe even wizards could notice this and freaking fix the bug MAYBE?
I doubt it though. Have a nice day.

Coolton u have 100% agreement of the community when saying this. We all wonder why wotc devs leaning back and ignoring this.

Stopped playing the game right after the beta. Came back due to various friends stating historic draft is 100 card brawl/commander. I spent a couple hours spending credits, grinding and spending card prints for a historic brawl deck. I can't even play the game mode due to this bug. I encountered the issue halfway through my color challenge unlocks, cleared the other two and nothing I can do will fix this issue.

How is it possible that Wizards cannot address a game progression bug that hinders new player experience! Isn't getting new players and making them happy with the game the primary goal of any game? I have been Magic cards since 2000 and now I was willing to start purchasing virtual cards but won't do it if I cannot even get through the White color challenge.

Talkinggoat did u try to remove and add cards to the deck? For some it worked. Did u ask to the support to fix it?

I'm having the same issue. I am stuck. Please fix this.

I was able to complete four of the five color challenges but the white one fifth match is broken. When I try to play it I get a network error, so I'm stuck with four single color decks until this gets resolved. I have tried on both PC (Windows) and Android.

I'm having the same problem, can't finish the color challenge.

can't finish color challenge (show network error) each time i try to do the last duel of the last color.

i restarted my game like 32 times this week. the error still remain

I'm a returning player. I did not get the base deck and could not complete color challenge

I can't complete any of the 5th duels for any color. Getting the network error bug. I've tried all of the things I've seen in forums and the steps WotC posted in their resources but nothing has worked. Please fix this for me. I really want to get back into Magic, but I don't want to spend money in an app that has this kind of issue.

Hola me pasa lo mismo que a todos necesito una solución por favor quiero seguir jugando, una vergüenza que le arruinen la experiencia a los jugadores nuevos.

Michbot try to manually remove cards from your decks and add new. Did U write the support to fix it for you?

Hi Wizards of the Coast, I am having the same issue, on both PC and iPad. I was able to complete the color challenge for 3 of the colors only, Blue and White do not allow me to complete the color challenge. I would love to complete these. Please help!

For months I have only ever received a network error when trying to complete the final portion of the Ajani Color challenge on my PC.

You can also contact support and they may be able to update your account from their end.

I am also having this issue and get the attached error