Slow
You alter time around up to six creatures of your choice in a 40- foot Cube within range. Each target must succeed on a Wisdom saving throw or be affected by this spell for the duration.
An affected target's Speed is halved, it takes a −2 penalty to AC and Dexterity saving throws, and it can't take Reactions. On its turns, it can take either an action or a Bonus Action, not both, and it can make only one attack if it takes the Attack action. If it casts a spell with a Somatic component, there is a 25 percent chance the spell fails as a result of the target making the spell's gestures too slowly.
An affected target repeats the save at the end of each of its turns, ending the spell on itself on a success.
Slow 5e 2024 vs. 2014 edition differences
The 2024 version adds "up to" duration, includes bard class, clarifies "Reactions" capitalization, and specifies a 25% chance of spell failure if casting a spell with Somatic components. It also states "make only one attack if it takes the Attack action," clarifying attack limits.