The Hand of Hemera is one of the four new wonder weapons on the map Ancient Evil. As is the case with many of the Zombie achievements in this game, this can be completed on Casual difficulty, so I would highly recommend using it over the other difficulties if you're going for this.
To begin, you'll need to find one of the four
Dormant Hands found scattered throughout the map. There are 20 spawn locations for them, all of which can be found in this video:
Alternatively, if you would like pictures of their locations,
this Reddit link will also show all 20.After you've found your first Dormant Hand, head to the
Monument of Craterus location of the map and look for the glowing yellow circle on the ground. Deposit your Dormant Hand into the statue and you'll begin a little ritual. It will require you to kill roughly 10 zombies that are glowing yellow in the chest, all the while you are required to stay within the glowing circle. After all 10 have been killed, you will be able to pick up the
Hand of Hemera. We're halfway there!
This weapon will need to be upgraded in order to use the charged ability required to unlock this achievement. In order to upgrade to the
Redeemed Hand of Hemera, you'll need to locate three mirrors located around the map, and shoot the Hand of Hemera off of them to collect a ball of light. The locations for the mirrors are as follows: the
Gymnasium Bathhouse, the
Upper Road, and the
Temple Terrace. When you find these mirrors, you will need to first shoot them with a normal gun in order to rotate them. Your goal is to make them be vertical, or as close as you can get to vertical. Once you've rotated them, shoot the Hand at the mirror, and you'll see the ball bounce off the mirror, into a crystal, and then to a nearby bowl. Melee the bowl and you'll see the light on your Hand. QUICKLY run back to the statue where we did the ritual and deposit the light by meleeing the bowls around it. If you're too slow the ball will fade from your gauntlet. No worries though, go back and shoot the mirror once more to try again. When you've successfully carried all three of them back to the statue, a portal will spawn that you need to enter.
This part is pretty straight forward, and is more or less a tutorial teaching you how to use the charged ability of the Redeemed version of the gauntlet. After killing the 30ish Zombies that spawn in, another portal will appear allowing you to exit with your newly upgraded Hand.
With the hard part out of the way, you now need to kill 20 zombies with one charged shot. This can easily be obtained anywhere you desire, but I find the easiest place to horde Zombies is in the
Amphitheater. Simply horde up 20-24 zombies, hold down
, and when you kill 20 in one go, the achievement will pop! If you don't manage to get 20 in one horde, keep holding down
and try to quickly find the remaining zombies needed. The achievement will pop when you let go of
If any of my steps were confusing to you, or if you just want a visual aid, be sure to check out this super quick (less than 2:00) video of a YouTuber named Glitch on how to build and upgrade the Hand of Hemera.