Arcane Disruptor

You have been afflicted with the rare and mysterious magic disease known as Weave Vision, which has given you a unique perspective on the nature of magic. You gain the following benefits:

• You focus your senses on the magical energy within 60 feet of you. You can use your Weave Vision as an action to sense the presence of magic and identify the school of magic (if any) and the strength of the magic (weak, moderate, or strong). Additionally, when you use this feature, you gain a form of truesight that allows you to see the magical auras of creatures that are affected by spells. This truesight lasts until the end of your turn.
• As a reaction, you can use your Spell Disruption to disrupt an enemy spellcaster's attempts to cast a spell. You focus your senses on the spellcaster, analyzing the magical energy they are manipulating. You then use your own innate magic to disrupt the spell, causing it to fail and any spell slot used to cast it to be expended as normal. Additionally, you are healed for an amount equal to the level of the spell being cast.

To use Spell Disruption, a creature within 60 feet of you must cast a spell. You must be able to see the creature and the spell being cast. The creature must make an Intelligence saving throw against your spell save DC. If they fail the check, the spell fails and any spell slot used to cast it is expended as normal.

After using Weave Vision or Spell Disruption, you must roll on the Arcane Disruptor Risk Table to determine the negative consequences you suffer. Roll 1d8 and consult the table below:

1. You are blinded until you complete a long rest.

2. You have disadvantage on ranged attack rolls until you complete a short or long rest.

3. You are unable to use magic for 1 minute.

4. You take 1d6 psychic damage.

5. You are deafened until you complete a short or long rest.

6. You are paralyzed until you succeed on a DC 15 Constitution saving throw.

7. You are frightened until you succeed on a DC 15 Wisdom saving throw.

8. You become stunned until the end of your next turn.

Once you have rolled on the risk table, you cannot use Spell Disruption again until you complete a short or long rest.
This feature is not a spell and cannot be targeted by counterspell. 

"The affliction known as Weave Vision is a rare and enigmatic magical disease, one that has fascinated and perplexed scholars of the arcane arts for generations. Those who suffer from this condition are gifted with an extraordinary ability to perceive the intricate threads and patterns that make up the very essence of magic. Among those afflicted with Weave Vision, there are a select few who have learned to harness this power and become known as Arcane Disruptors. These individuals possess the ability to disrupt enemy spellcasting and protect themselves and their allies from the most potent magical attacks. However, the price of this power is high. Those who suffer from Weave Vision experience a multitude of debilitating side effects, including blindness and other physical ailments. The risks of mastery are great, and only the most determined and dedicated practitioners are able to overcome them. The mysteries and complexities of this affliction continue to elude us, but each new discovery brings us closer to understanding the true nature of magic itself. Those who seek to master these abilities must be prepared to pay a steep price, but the rewards of such mastery are beyond measure." - Elminster Aumar, the Sage of Shadowdale