Sorry, D&D 2024 Dungeon Masters: Feats and Multiclassing are no longer optional rules and they don't require your permission
Multiclassing in Dungeons & Dragons has been around since Advanced D&D 1st Edition in 1977. Multiclassing is when a character goes up in level but takes a level in a different character class. A 1st level Fighter hits second level and then, instead of becoming a 2nd level Fighter, takes a level in Rogue, thus becoming a multiclass Fighter 1/Rogue 1. If you meet the minimum prerequisites to become a third, fourth, or even fifth class (I'm not sure there's a limit), then you can multiclass until the cows come home.
But it was always an optional rule. Optional. One that required your Dungeon Master's permission to get into. Multiclassing was also optional in Advanced D&D 2nd Edition. In 3rd Edition and 3rd Edition Revised (3.5), multiclassing became a standard rule and more widely accessible. While it became a core rule, requesting your DM's permission was still implicit. 4th Edition was different. Multiclassing was a hybridized system of taking Feats that allowed characters to gain features from other classes. But in 5th Edition, perhaps to simplify gameplay, multiclassing was once again an optional rule. A rule that required express permission from your DM to use.
But in the D&D 2024 Player's Handbook, any language hinting that multiclassing is optional (or even requires your DM's permission) has been removed.
D&D 5e: "With the DM's permission."
D&D 2024: ...
D&D 5e: "Optional sets of rules."
D&D 2024: [silence]
D&D 5e: "Your DM decides whether these options are available in a campaign."
D&D 2024: *sips tea*
Feats were likewise an optional rule in vanilla 5e. Their inclusion is in the 5e Player's Handbook, yes, but in a separate chapter for Customization Options. "Options" meaning they aren't a core rule. No, Feats and Multiclassing are not optional rules buried in the Dungeon Master's Guide—where objectively very few people ever read them, let alone remember them. Feats and Multiclassing are indeed dangled in front of player's faces in the aptly titled Player's Handbook. So, D&D's designers most certainly wanted these "optional" rules to be very accessible to players.
But the entire redesign the D&D 2024 PHB undergoes makes it explicit that Feats and Multiclassing aren't up to your DM anymore. They're a core rule now. In fact, your players may not even mention their intentions to multiclass until they hit a new level and decide to create that very popular, very overpowered multiclass combination. You'll just show up at the table one day and find out that your favorite Sorcerer is now a Sorlock (a Sorcerer/Warlock), or the confusingly named mirror image of that, the Warlock/Sorcerer (a "Coffeelock" for some reason). There's the Hexadin (a Hexblade Warlock/Paladin). A Barbarian/Paladin (Barbadin).
Paladins and Sorcerers are far and away the most popular multiclassing options. Which is probably indicative of how OP those multiclassing options are.
As a current Dungeon Master, I'm acting like I had some stranglehold on my players' character creation process. I know I'm making it sound like I have anything to do with their leveling-up options. But in reality: I don't. My players are always going to do what they want to do, and it doesn't even cross their minds—heck, it doesn't cross my mind—that they should ask my permission to do it. So, while the D&D 2024 PHB, hitting store shelves on September 17, acts like players don't need your permission to take Feats or Multiclass, they probably weren't asking your permission before.
I just have to remember a useful bit of advice every '90s rapper taught me: Don't hate the player, hate the game.
