Gems of War

Following the other guide, some percentage of your Explore boss battles will now be Mimic battles.

Solution for Mimic Menagerie In Gems of War

My current working assumption is that the Mimic replacement is about 10% (1/10), possibly less, but as with all odds without pity timers, you can do this 100 times and never get lucky, so there's no way to know how long it's going to take anyone in particular. For example, I went 26 boss chests between Mimics as I attempted to earn this achievement. That's unlucky, but not unreasonably so.

Once you do have a Mimic battle, however, there's a chance that upon completion you'll get a Hoard Mimic battle. Since this is a rare-ish event following a similiarly rare-ish event, the exact odds here are also hard to know. But I've seen reported battles that would indicate the second tier battle may be more common (relative to Mimics), though this would still represent a MUCH lower than 10% chance. Possibly as low as 1%.

Now the worse news. A Boss Chest does not drop the troop card at 100% either. This means this achievement is behind three different layers of RNG, each impacting your odds of it happening by an unknown percentage. If each of the three tiers was a 10% chance, each explore result that netted a boss chest to would be a 0.1% chance (1/1000) to earn this achievement. The actual odds are likely higher since the frequency of horde cards to horde mimics seems to indicate that it's higher than 10%, but with the small sample size to date, that could still be wrong.

Lower level explores will take more battles overall to get those mythstones, as usual, while if they grant a Mimic battle, the Mimic is at E12, so E12 is definitely the right choice, if you can manage it.

This is a very rare event and most of those who have unlocked it so far have gotten very lucky or at least moderately lucky while also grinding a bunch. Over time we'll likely get more data to accurately paint a picture of the odds, and I'm continuing to monitor the data from several sources, including the comments. If I see something that gives me a better guess as to the odds, I'll update this solution further. In the meantime, all I can say definitively is that will (usually) take a LOT of exploring to get.

My data as of 2022-03-18:
118 Total Boss Chests since the patch
106 Normal results
11 Mimics (9.32%)
1 Horde Mimics (0.08%)

Not so much a solution but as a warning:

Unless you intend on grinding this out for years and go through hundreds and hundreds of level 12 explore runs, don't bother attempting this. Unless you can purchase it via real money on some event or in the shop, you have almost zero chance of getting this. Barring some changes that increase the odds of getting this, I think this achievement is a cruel joke by the developers and not a funny one at all.

The Hoard Mimic Troop is a Mythic troop (From Dragon's Claw BTW) that is gained through a Hoard Mimic Battle triggered by a Boss Chest. The Boss Chest is unlocked after beating a Mythic Boss Battle in explore run which costs 100 Mythstones. The Mythic Boss Battles at Explore level 12 are difficult enough but just getting ANY Hoard Mimic Battle at all is extremely rare. I've played hundreds of Level 12 explore runs (while earning tokens, badges, and medals) and only got a handful of Mimic Hoard Battles at all since January 2022. None of them gave me the Hoard Mimic Troop. None!

I don't like discouraging other gamers from attempting achievements and generally am persistent (even if I go through episodes of rage-quitting for a while) but considering how extremely rare it is to get even any mimic hoard battle, you probably have a greater chance of meteors, satellite debris, or a plane crashing onto your front or back yard on a given day than you have at unlocking this achievement.

Completely unacceptable and a horrible joke...

UPDATE as of January 9, 2024: I've made it more than halfway towards the infamous "Try This One Geoff" achievement and still zero Hoard Mimic.