Counterspell

Reaction, '30 feet
You attempt to interrupt a creature that you
can see casting a spell. If the creature is casting
a spell of 3rd level or lower, its spell fails and
has no effect. If it's a spell of 4th level or higher,
make a check using your spellcasting ability.
The DC is 10 + the spell's level.
At Higher Levels: The interrupted spell has no
effect if its level is less than or equal to the level
of the spell slot you used.