25 Jun Counterspell 5e D&D Guide 
Counterspell can be the saving grace in a heated conflict between the big bad and any adventuring group. The ability to mitigate a potential game-ending spell before it takes effect is the perfect reason to make sure Counterspell is in the book.
The rules for Counterspell can be found in the Players Handbook on page 228.
Abjuration 3rd level
Casting Time: 1 Reaction
Range: 60 Feet
You attempt to interrupt a creature in the process of casting a spell. If the creature is casting a spell of 3rd level or lower, its spell fails and has no effect. If it is casting a spell of 4th level or higher, make an ability check using your spellcasting ability. The DC equals 10 + the spell’s level. On a success, the creature’s spell fails and has no effect.
At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the interrupted spell has no effect if its level is less than or equal to the level of the spell slot you used.
The rules for Counterspell show the spell is only available as a reaction. Unlike other spells, the success of Counterspell can be determined by die roll versus the spell level. This can make the use of the spell risky but well worth it when it works.
Is Counterspell Good?
Counterspell gives the savvy caster the opportunity to completely cancel an enemy’s spell. It is triggered as a reaction to the opposing caster in the process of casting a spell.
This means if successful, the opposition has failed to cast the spell resulting in no effect, and they have lost the spell slot used to cast the spell. The fact that it uses a reaction also means the caster does not need to hold an action to make it work and allows them to cast two spells on the same turn.
Using Counterspell has significant advantages since it can potentially counter any spell in the game as soon as it’s available. That does not mean it is free from risk. Counterspell uses a minimum 3rd level spell slot.
If it fails, the spell is wasted, and the enemy still gets to cast their spell. Proper use of the spell relies on some smart planning and decisions on the part of the caster. The higher the casting level of the Counterspell, the more likely there will be an automatic success, but it is not guaranteed.
Can You Counterspell a Counterspell?
Counterspell counters a spell and is a spell itself, so absolutely it is possible to counter a Counterspell. This, of course, depends on having a reaction available to do so. Counterspell can be used to counter any spell that you are aware of being cast. This includes scrolls, wands, staffs, and any other spell you can discern.
How Does Counterspell Work?
Counterspell is cast as a reaction to another spell being cast. At the time the counter attempt is made, the mage declares the level at which Counterspell is cast. If the spell to be countered is of the declared level or lower, it is automatically dispelled. For example, a Counterspell of level 5 will counter all spells level 5 and lower automatically.
If the spell is a higher level than the attempted Counterspell, a check is made. The Counterspell caster rolls a d20 + the spellcasting ability modifier against a DC of the cast spell level + 10. There are no additional bonuses added to either roll. If the Counterspell total is higher than the Difficulty Class(DC), the spell is canceled.
The Abjuration Arcane Tradition Wizard is the exception to this rule. At level 10, they gain the ability to add their proficiency modifier to Abjuration spells. This includes Counterspell and Dispel Magic.
Counterspell: Innate Spell Casting, and Spell-Like Abilities
Two interesting points of contention are Innate Spell Casting features and Spell-Like abilities from monsters. These two items function similarly to spells but differ slightly enough to cause some confusion. Generally, 5e is specific on the wording used to garner clarification.
Innate spell casting represents a creature’s ability to recreate spell effects naturally. It is usually reserved for intelligent monsters or enemies that can simulate casting a spell in some way. This means that a mage could attempt to Counterspell an innate spell casting ability.
Spell-Like abilities are not spells; they are natural abilities of creatures that mimic magic. These are usually applied to unintelligent monsters or enemies. For example, a Crag Cat has a spell turning ability that is not able to be Counterspelled. The same could be said for an Umberhulk and their confusion-like ability.
Counterspell can be one of the most frustrating spells out there for a mage. It seems like a waste to prepare if it doesn’t come up. Much like Dispel Magic, it strongly depends on the game scenario on how effective it will be.
That being said, it is hard to pass up the opportunity to take it when it’s available. The satisfaction of stopping a game-changing enemy spell in its tracks and saving the party is pretty exhilarating.