Blinded

The Blinded condition is an extremely potent debuff and can be a massive headache for nearly every creature in a fight. The primary target for these effects are Melee and Ranged combatants as they will suffer from disadvantaged attacks while creatures attacking them have advantage.
Magic users will be slightly less concerned by the effects of the Blinded condition. Ranged spell attacks or attacks that contain the verbiage “a creature you can see” will certainly suffer from the results of being blinded, but there are plenty of spells, such as the infamous Fireball, that won’t be affected because they target an area of effect.

Exceptions

When attempting to blind a creature, make sure to consider if they have Blindsight or Tremorsense, as both of these abilities can be used to perceive surroundings without relying on sight. For Blindsight, creatures without eyes, such as grimlocks and gray oozes, typically have this special sense, as do creatures with echolocation or heightened senses, such as bats and true dragons. Tremorsense, on the other hand, mainly belongs to burrowing creatures such as worms and moles.

Methods

Some examples of things that can apply the Blinded condition are:

• Blindness/Deafness (spell)
• Blinding Smite (spell)
• Sunburst (spell)

Blinded Condition

• A blinded creature can’t see and automatically fails any ability check that requires sight.
• • Attack rolls against the creature have advantage, and the creature’s attack rolls have disadvantage.