Hex
You place a curse on a creature that you can see within range. Until the spell ends, you deal an extra 1d6 Necrotic damage to the target whenever you hit it with an attack roll. Also, choose one ability when you cast the spell. The target has Disadvantage on ability checks made with the chosen ability.
If the target drops to 0 Hit Points before this spell ends, you can use a Bonus Action on a later turn to curse a new creature.
Using a Higher-Level Spell Slot. Your Concentration can last longer with a spell slot of level 2 (up to 4 hours), 3-4 (up to 8 hours), or 5+ (up to 24 hours).
Hex 5.5e 2024 vs. 5e 2014 edition differences
The 2024 version clarifies that the extra damage occurs on attack rolls, not hits, and specifies that Disadvantage applies to ability checks with the chosen ability. It also states concentration duration increases with spell slot level: 2nd level (up to 4 hours), 3-4 (up to 8 hours), 5+ (up to 24 hours).