I'm in support, it's a nice way for newbies to get a head start.
It's a little hectic trying to trade for the rare outcome during the month when demand is high- but afterward it's usually a lot easier.
I do wonder whether a notice similar to Dec 18th would be warranted if it's going to be more frequent, though. It seems like it might be easy for newbies to be tricked into a 1:1 litter swap.
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For those not supporting because they aim for a full collection and find these types of litters frustrating-
I don't understand why rarer monthly outcomes would be a problem, when the main barrier to a complete collection is in the older releases?
I mean this in a respectful way, but complete collections are never ever happening for a majority of players, and those older pets are the main reason why. I joined in 2011 and I've amassed a decent collection over the years- but completing it feels as improbable as it did when I joined. Not impossible- but comparable in my eyes to something like, a full shiny pokedex; more of a badge of honor than a required checkbox, y'know?
Personally, I take this as a positive, and it removes the completionist stress, but I get that others may see it different.