This guide is more of an add on to the first guide by Zenész, but too long to have as just a comment on his.
Here are some quick tips that I've learned from the teams I've been on that I haven't seen mentioned yet...
Have the host get Firepower at the fate room. Below is a link you can use to tell the differences between the rocks.https://www.reddit.com/r/DeadOpsArcade3/comments/jyhvhm/room
I believe the only way to see the stones in their "true form" is to donate a key to the well. The location of the well is on the circular path up the volcano making your way towards the fate room. You will see a skinny white bridge about halfway up with spikes on it. You will need to cross it. On the right-hand side after you cross the bridge should be the well to donate the key. AFTER you've done that, you should be able to tell the difference in some of the fate stones. It MAY NOT reveal the difference between all the stones. I know it should reveal at least one of the stones.
Next is the strategy my team used to get this done. I was not the one who came up with it. It is much easier done with 4 players and at least two Xbox series x/s. Player 1 (Host), Player 2 (Xbox series x), Player 3 (Xbox series x), Player 4. Player 1 and 4's Xbox's do not really matter. We played normally until we got to higher rounds (40-50) when we started to normally die off and have to keep rejoining. Once we got to that point, then started using this strategy for the rest of the game. Though you and your team can decide to use it as early or late as you want.
At the end of a round make sure Player 2,3,4 all have full lives. If they do not, leave and rejoin the game. While one of the players is out of the lobby, have Player 1(host) send a bunch of join game invites to the team. Make sure Player 1(the host) has 0 lives. Once plenty have game invites have been sent to everyone from the host, everyone has refreshed lives, and the host has 0 lives, you are ready to start the next round.
At the start of the new round you will have player 1 go down at the beginning. Player 2 will donate one of his lives to pick player 1 back up. Doing so will reward him with power drops. Usually boxing gloves. These are the key to the strategy. Once you have the boxing gloves you want to stay in one spot and keep spinning around as fast as you can like a tornado. The rest of the team will stand right next to player 2 while he is spinning around taking out everything. The team will still be shooting at zombies, meatballs, red tank zombies, and anything else coming your way. The boxing gloves last about 20 seconds.
After Player 1 has been revived the first time, he wants to run around and take out everything he can while he has the small amount of invincibility. Once that wears off, he wants to go down again as quickly as possible. Player 2 will then time picking him up towards the end of his boxing gloves running out. If done correctly, he will never run out of boxing gloves during his turn and will also make them last as long as possible. Player 2 will repeat this until they have no more lives. When they run out of lives BUT still have their gloves up, Player 3 will step in and do the same thing. When player 3 donates a life to player 1 he will get the chance at gloves. Once player 3 has gloves player two immediately drops his nuke and quits the game. From there he joins off of player 1's game invites before the round started.
The reason for trying to do this with at least 2 new Xbox's is because they can quit and rejoin the game incredibly fast. It takes roughly 15 seconds for them. Versus the Xbox One may take 30-60 seconds.
Player 3 will now go through his lives donating them to the host, getting gloves, circling. By the time he is done, player 2 should be back. If they are not, player 4 can take their turn. We tended to have player 4 as a backup option/safety net because they had an Xbox One and could not join back in fast. Rense and repeat until the round is over. Once that happens, have everyone leave and come back at separate times to refresh their lives but not leave the host vulnerable from accidentally going down since they have 0 lives.
There are some significant risks to doing this strategy if it's not done properly. If someone is AFK, timing is not done well, or people are not paying attention/focused, it is very easy for all hell to break loose and down the whole team. This whole strategy relies on good timing between the players going down, getting gloves continuously, passing the glove responsibility on to the next player, leaving, and coming back in. If your team is having major trouble doing this, this strategy won't work for you. You can also practice it with your team in the early rounds to get the hang of it.
You also want player 1(host) to be collecting nukes as you progress through all the earlier rounds. They should have 9 nukes and 0 lives by the time they reach the boss fight at wave 64. I'll explain this later on.
It is not guaranteed that boxing gloves will drop when you donate a life. Sometimes you will get a pack a punched weapon. If this happens, the host needs to go down as quickly as possible again and you need to donate another life. Keep doing that until you get the gloves. I'd say we got the gloves about 80-90% of the time we donated our lives.
The gloves will not take out the bigger zombies, special zombies, etc. that I mentioned earlier. So make sure the players that are not spinning gloves at that time focus their guns on those.
Certain spots are better for hoarding the zombies too. On the level with the house, grass, and lawnmower there is a spot at the top of the map next to a fence. You can climb on a lawn chair to climb over the fence to get to it. This is a great spot since they can now only come down the hall and the door in the middle.
Another good spot when doing this strategy on one of the last levels with the fireballs all over would be on the circular-shaped part on the wooden walkway. Zombies can only come from two spots there.
One of my early playthroughs we finished wave 60. After that is a Wild spot. At some point during the Wild area it caused our hosts xbox to crash and ended the game for all of us. In the session I got the achievement 2 of the 4 players back out and rejoined as the other 2 players entered the wild. The 2 joining will sit in a black screen until the other 2 players finish the wild and get to the next round. BUT that allows the players going through the wild to have infinite revives since the game is registering 4 players in the game but only two are actually going through the Wild at that time.
Wave 61 strategy.
When the save starts you will face a Margwa. Have player 2 or 3 constantly join in and leave the game just dropping their nukes. Don't worry about the lives. Just drop the nuke, quit, rejoin. This allows the other 3 players time to focus their firepower on the Margwa until it's done. Once it's done have all the players stay in and resume the boxing glove strategy.
Wave 64 strategy.
This will be a normal zombie round at first. Use the boxing glove strategy here until you see the red text on your screen saying the Boss Battle is happening. From this point on be very careful leaving and joining back in. If you are not back in the game when the boss is killed you will not get the achievement. Everyone should use their nukes one at a time. Similar to the nuke strategy in wave 61 but without leaving and coming back if possible. Then player 1(host) will have their 9 nukes and start using them efficiently. This allows the whole team to focus their firepower on the boss without having to worry too much about the zombies. If you find your team losing lives quickly then have the players that can leave and join quickly do so. But be very careful.
ALWAYS try to leave at least one person with lives in the game with player one(host) until someone else has joined back. If player one goes down and nobody is in there with them that is up, that's game over.
Even using this strategy, this is not an easy achievement to get in my opinion. If people are not focused or not pulling their own weight, it will be very difficult.
I'll add anything else to this as I remember it. Please let me know if there is anything I can clarify or missed too. Good luck to all of you!