I just canāt wait to play malibu barbie with my heroes. 
I await this with cautious pessimism and really not all that interested in them.
I just hope that this is tolerable enough to not force my hand to leave the game. Finally feeling bored of spending money for heroes I am not lucky enough to pull.
Ah, I see, they updated it with the image while I was eating my apple.
So Vivica is now Zatanna?
Yes she is 
Careful you donāt choke on the headphone jackā¦oh wait 
Lots of opinions here on something that hasnāt even started yet!
Costumes were fun in beta and the user interface is nice. Iām not entirely sold on them. But I will spend gems, Tibs and BT are emblemed up on my red/purple raiding teams, so the chance for a permanent 5-10% stat boost for each is too good to pass up.
Go in with an open mind, and remember this is a game, itās supposed to be funā¦ and anyway, nobodyās making you spend anything 
Some people find barbieās dreamhouse to be fun. Some people enjoy paper dolls and playdoh. Some people are also 6 years old.
Everyoneās definition of fun is different.
The underlying problem with costumes is that, at their heart, they are NOT fun. You are not just given some skins to switch on and off. That would be considered āfunā rather than āOh, hereās some more crap to grind forā and āoh, you can get a free draw if you likeā¦ but yeah letās go ahead and give you the āchoiceā to spend even more money to ātryā for these thingsā
Is it fun if you have the costume, youāve grinded for the mats/resources and leveled it? Debatable. My opinion of most of these costumes is that they are santa-level bad. (referencing the artwork departure of the xmas heroes from the rest). Iāll take the bonuses (for some of them) but does my hero really have to look that stupid?
I dunno. itās just another thing. Except that this thing is both rare AND stupid-looking that will require MORE grinding if I wish to remain competitive.
Do I have to play? No.
Does it force me to question my interest? Increasingly.
So is that implying that Iām childish for intending to utilise this new feature?
Not at all. Just reinforcing that I am personally disinterested and disenchanted.
Can we use any of the heroes for the costume event @zephyr1 or limited to the released costumed heroes.
Yes, there are no restrictions on heroes.
Is the costume portal a separate portal, or does it replace a portal while active?
Yes, itās actually completely separate. It doesnāt even appear in the Summons window, it has a separate icon and popup.
Can I just say again, bless you Zeph for being such a great conduit of knowledge on this and other topics.
Your efforts to clarify and demystify controversial new content are invaluable.
Originally in beta, the description on the costume keys mentioned sources other than the Costume Quest. However, more recent versions had those sources removed from the description.
Therefore, itās my assumption quests will be the only source.
Oh wt f, costumes have to be leveled too? Itās not enough to just pull a Legendary key? I didnāt see the converstion rates but Iām already not feeling it.
Donāt forget Alchemy Lab but I guess thatās a close 2nd to tourney loot.
14 summons a yearā¦ is that correct?
Alchemy lab is the biggest disappointment as it is practically useless.
Raid tournaments in my eyes were the best invention in 2019. All players can compete at least in some of the tournaments and the loot, even though it had been reduced, is still pretty great for Top 1 and 5 %.
What I like most is that itās mostly about activity and skill. As a good player you can make it to the top loot tiers of 2-4* tourneys most of the time and even in 5* tournaments itās possible to be somewhat competitive when you have mostly trainable heroes and only few HoTM or event 5*.
However, for costumes activity does hardly matter at all unless there are other ways to get them or the summon keysā¦ Yes, you can accumulate gems via grinding but thatās only like 600 a month for very active diamond raid arena players, in other words a less than 10 % chance per month to get a legendary costume which might even be one that cannot be used as the corresponding hero isnāt in your roster.And most F2P and C2P will need their gems more for summonimg heroes I supposeā¦
From the announcement, it seems the portal opens 12 times a year (3rd Monday of each month with an opening of 48 hours each time). I am sure you know whatās coming though. From the SGG standpoint, during this time, you can summon ala AYCS (All You Care to Summon) to your heartās desire as long as you have enough keys or willing to spend the gems. 
Some people may disagree with me but I actually like that the costumeās level canāt be higher than the original heroās level. Otherwise, you could just leave your original hero at 1-1 and level up the costume instead. In this way, it is more fair to people who have already maxed the hero.
I also like that no 4* mats are required for the costumes.
What I hate as FTP, though, is that the major source of costumes are summons (ācostume chamberā). The costume quests should either give more keys or/and we should be able to get keys from gameplay (titans, AW, chests, event completion rewards).
Between the wording of your answer and Boldtuskās costume, I couldnāt help but think of this:
