Yeah. Just speculation, but with the new stuff in preparation (War of Three Kingdoms, Soul Exchange etc) they preferred to keep a completely new event for the months when they might not have a lot of new content.
And the challange festival will still include 3 new costumes, so it would bring them more revenues than Starfall Circus which does not include new heroes
Good news for me. I got almost everything I wanted out of it last time. Gives me more time to save free challenge coins for Starfall Circus, which is the next event where I am targeting heroes.
I will add it to the OP later today.
Hello Play, I cant find Challenge festival offers on main paige.
Where can I find them?
Thank you!
It has the standard Challange Event offers:
Source: @VeryQuietly 's Quick Monthly Reference:
That’s seriously a lot of well-organized information in a single infographic, @VeryQuietly ! Nicely done! The only information that I don’t see that I am usually interested in is the type of emblems included in the challenge event’s completion rewards. (I typically just go for completion.) Not sure if that’s something you’d want to try and squeeze in or not.
I finally pulled this guy with my saved coins who will boost my red event team nicely!
Only Peters left and then I’ll have collected all the 4* heroes from the old events!
Had 3 free pulls with coins collected from previous 2 events. 3rd Falcon, 5th Jackal and this:
Especially with the costume, that defense down yellow looks far better than costume Vivica. Not that I have her or anything.
Edit: Also that is one ugly costume art.
Woot! Guardian Gazelle & a second Jackal & 2 more Treevils in a 10-pull.
Hey Play, can we predict next time challenge festival will show again?
Around june/july probably?
Thanks 
Did 10-pull. Iris, Gnomer, and Lemur as new heroes. It’s ok
I think I’ll save my coins.
Most non 5* heroes can be obtained using HA…
Why is it so hard to get Treevil??? I did 2 10-pulls, wasn’t hoping for any 5s (just as well, because I didn’t get any except Iris). I pulled at least one of each of the other new 3*s (all of which I have maxed), but still no Treevil…
I’m not being greedy when I just want a 3*, right?
On first pull got Costume Maria Teresa.
Thats probably my summoning done for the event.
Also had a mini panic when doing rare final level. Got to bosses and realised i’d forgotten to bring a healer. Threw arrows and axes and made it through alive…
That was an amazing 10 pull! Congrats 
.
Did a 10 pull as well, no expectations but always hopeful …
