Wizards of the Coast clearly puts serious consideration and planning into introducing new elements to Dungeons & Dragons each time a new expansion releases. However, outside these massive expansions or D&D's new editions, the developer will often make smaller additions to everything from class archetypes to magic spells to the lore of the series through Unearthed Arcana.
These mini-updates known as Unearthed Arcana take the form of articles released directly by Wizards of the Coast to the official Dungeons & Dragons website. While the canon of these articles and the changes they can make to some player characters and monsters are often considered tenuous, they can inform how the development of the game might proceed going into the next edition.
Before getting into the best things that Unearthed Arcana can add to Dungeons & Dragons 6E, it should be clearly defined what these articles amount to in terms of game design. These are essentially beta concepts for the game that haven't quite been refined to the point of being included in an official rule book, but are instead presented for players and DMs to play around with and test for themselves. Many players consider these rules to be a form of Wizards of the Coast guided Homebrew, with all the caveats that comes with the practice.
Hand of Radiance
It can be a difficult sell from a party or DM to convince one player to take the role of a Cleric, especially for new players that are excited to jump into combat and start killing low-level enemies. So, introducing a solid form of damage that the class can use as a cantrip can make the idea of taking what some players might assume to be a passive class into a walking force of destruction. In that case, the Hand of Radiance spell introduced through Unearthed Arcana 36 can be an impressive addition to Dungeons & Dragons' best Cleric builds.
The spell Hand of Radiance itself causes any creature that the Cleric chooses within five feet to take 1D6 radiant damage, with the caveat of the enemy possibly avoiding damage on a successful Constitution saving throw. Considering that Clerics are already a tanky class, with medium armor and shields from the start, this can make the class' utility jump from just a single cantrip that will also improve every few levels. While the idea that Clerics differ from Paladins by being squishy healers is a misconception, giving players access to this type of magical combat so early on can lead to crafting powerful builds.
Puppet
Another impressive spell introduced in Unearthed Arcana 36 is Puppet, which allows Bards, Warlocks, and Wizards to force a charmable target to move in any direction and drop whatever they are holding. As it currently exists within the rules of Unearthed Arcana, this is a 1st level spell and acts as a way of giving other spell casters a weakened form of the Command spell available to Clerics, Paladins, and Bards. However, the addition of being able to disarm targets as well as sending them away makes it overpowered as a 1st level spell, especially for higher level Wizard builds that can abuse it as a signature spell.
To better balance the spell into Dungeons & Dragons 6E, this should either be raised to a 3rd-level spell, removing it from being overly abused, or force the caster to choose between movement and disarming. Considering that disarming most humanoid enemies can almost completely remove their combat abilities, being able to spam this spell could carry most parties through encounters on its own. So, as fun as it would be to spam disarm with high level magic classes, trivializing combat with humanoid enemies would make it a poorly balanced spell.
The Mystic Class
Adding classes in Dungeons and Dragons 6E is likely the biggest change on the minds of players, with some hoping to see Homebrew classes like the Blood Hunter appear as an official option. However, pulling away from what players have developed, Wizards of the Coast already has a handful of classes that could easily fit into a new edition of the game. The new Mystic class introduced in Unearthed Arcana 32 could be the perfect addition to the next evolution of D&D, especially with the ways the 5E has already laid the groundwork for Psionic based subclasses and abilities.
As a whole, the Mystic class is possibly one of the most malleable, with several of its abilities and class archetypes being able to change proficiencies from day to day. The biggest issue to iron out would be how powerful the Order of the Immortal currently is, with its seeming inability to die making it one that is the most ripe for abuse and tempting to gravitate towards. So, while there are kinks to work out before introducing the Mystic into Dungeons & Dragons 6E, it is easily one of the most impressive classes that could come out of the Unearthed Arcana beta grounds and into the base game.
Technomagic
This could easily be one of the most controversial additions if made canon in Dungeons & Dragons 6E, given what bringing Unearthed Arcana 7 into the base game would mean for lore, world crafting, and gameplay. The addition of modern magic that is usable on electronic technology and computers would either mean bringing computers back to the more ancient settings of D&D, or making a universe like the Netflix film Bright with monsters and magic in modern times. However, what this means for the lore is nothing compared to how much this opens up the options for creating never before seen stories and expanding into alternative markets.
Including modern magic from Unearthed Arcana 7, and the implied modern world that it entails, could bridge the gap for fans of other tabletop titles like Call of Cthulhu or Cyberpunk 2077. Considering the impact some of these games have on foreign markets, like Call of Cthulhu's domination of Japan, following in these competitors footsteps could bring more fans to Dungeons & Dragons 6E. In this way, the beta attempts to bring modern magic into the game could allow Unearthed Arcana to inform the next evolution of D&D.
Dungeons and Dragons 5E is available now.