Don't implement the Deck of Many Things unless you are ready to face the consequences.

I got attached to my character just in time for drama to shelf the campaign.

The deck is a great toy, but you have to realize its limitations, prepare the players, and never, ever let it be an unknown. The characters should always be aware that it exists and it should have a reputation in game just as bad as it does in real life.

You tell the players ahead of any possible pull that it's optional, that some of the effects are ruinous to a character, and that there's no take backs. Make very certain that they know that the odds are only slightly better than Russian roulette, and that the outcome can be just as drastic for their characters.

If you aren't willing to put that kind of effort into them gambling in a way that can fuck up the campaign/adventure/world you're running, then don't use it at all.

You can nerf the deck instead, changing or removing the extremes. But that takes the "fun" out of it. And there are people that love the rng craziness of it.

If it's done right it is fun. But it's so easy to do it wrong that it isn't usually worth it when you can get similar results with good storytelling

People have no clue how to use the deck. Remove or modify cards that would negatively impact your campaign, work the newly introduced aspects into your intended storyline before you even offer it, ask for consent beforehand, and accept that your campaign will go off the rails for several sessions. The deck is often used similarly to opening up your relationship in its waning hours- it is the death knell, not the murder implement.

The DoMT is a magnet for doomed campaigns. Speaking from experience as a DM and a Player. I've only ever seen it implemented well once, and that's only because the DM wrote the rest of the campaign like a book after the group drifted apart.

As a player and a first time DM, I did not like it at all when my DM brought out the DoMT. First off, a player was given the deck outside the context of the game, so we're all (characters) sitting at a bar when out of nowhere one of us pulls this deck of cards out that none of us had ever seen before. Then (because RP goes out the window when you have the opportunity to use a new real-life toy) everyone in the party decided to pull one, causing one person to get 3 wishes, another to get a follower, and (after peer pressuring me) my character (a punk rock vampire!) to have his alignment changed to lawful good.

That was 3 sessions ago and since then every game has been non-stop gimmicks to cater to the results of the deck pull. One player is leaving (partly for this but for a few other reasons) and the game is slowly drifting apart; I completely blame the DoMT (and my DM's poor implementation) for the likely death of my first DnD campaign 😞

The DM of that game is a player in the game I'm running. He asked if I'd like to borrow the deck.. had to politely decline. "too complicated for a first timer" I told him. "and it's dumb as shit and only makes things interesting when you've made them boring," I did not tell him.