Countercaster

Countercasters are a rare and unique few, largely because the study requires a contradiction. You must have the drive and willingness to learn and perfect your arcane craft, but must also dedicate yourself to the destruction of that very topic. Perhaps your life was ruined by a powerful caster, and you do not mind your methods of revenge. Maybe you have simply found ways to invert and alter your formulas to produce new, contradictory effects. Or it might be that you simply find yourself overrun with nefarious magic and pesky casters, and training against them is the most prudent option. However you found yourself down this path, you are keen with your understanding and quick with your spells, and you will make magic users dread these facts.

Studied Recall

After significant time and study, you know the intricacies of dozens of spells off the top of your head. Beginning at 2nd level, when you see a spell being cast with either verbal or somatic components, you can attempt to recognize the spell before it is released. When a spell is cast, have the DM take the spell's base level and add three, or 0 if it’s a cantrip. If this number is equal to or below your arcana modifier, your recognize the spell and it’s effects before it is cast. If the DM rules that you cannot know about the spell, but its number is still below your arcana modifier, they must still tell you at least one type of damage the spell deals, if any.

Defensive casting

Starting at 2nd level, when you can see a creature or object become targeted by an effect that would deal any of the damage types below (this includes traps, attacks, spells, etc), you can instinctually cast a spell to nullify its effects. Using your reaction, you can cast a spell or cantrip with a casting time of an action or bonus action, so long as this spell has a duration of instantaneous, immediately deals a damage type counter to the triggering effect, and it overlaps with the triggering effect for at least one creature or object. Have both effects roll for damage. Take whichever damage total is higher, and subtract the smaller total from that, creatures effected by both effects is now only targeted by the effect with the higher damage output and only takes the newly calculated damage. If a spell or effect has all of its damage reduced to 0, it can no longer produce additional effects, regardless of a hit or save, such as the movement speed reduction of Ray of Frost. If either effect has an area of effect that targets a creature outside of the influence of the other effect, it deals its normal amount of damage. The turn after you’ve used this reaction, you lose either your action or bonus action, whichever the reaction spell should have consumed.

Fire-cold
Radiant-necrotic
Thunder-force
Bludgeoning/piercing/slashing-bludgeoning/piercing/slashing

Your DM may rule that some spells, such as create water, may be eligible for defensive casting against certain triggers or damage types, like fire. If the spell does not already deal damage, assume it nullifies an amount of damage equal to 1d8 per one plus the level the spell was cast at, unless it is a cantrip, in which case it is only 1d8

Enhanced Recall

At 6th level, when you use your Studied Recall feature, the DM must also add 5 plus the level this spell was cast at, if this new number is equal to or below your arcana modifer, you also know the level the spell is cast at. Alternatively, if the spell is a cantrip, you learn how many damage dice, if any, it rolls on a success.

Invert Arcana

After restlessly studying the strange magics of the world, you have learned to reverse the effects of certain spells, making gaps in arcane energy where they were supposed to well up with it. At 6th level, you may now invoke your Defensive Casting feature against any damage type, so long as you cast a spell that deals the same damage type and follows the other rules of Defensive Casting. If you counter in this way, with damage pairs not listed above, then your spell can deal no damage, but will instead only nullify the triggering effect’s damage, to a minimum of 0.

Rapid Spellwork

Starting at 10th level, your mastery over your spells has ascended beyond simple swiftness. Your Defensive Casting feature now no longer uses your reaction, but it may still only be used once per round, and cannot be used if you are surprised or incapacitated.

Dismantle Arcana

Starting at 10th level, when you cast Counterspell or Dispel Magic, the spell is considered upcast by a level determined by half your proficiency bonus rounded down, this does not expend the higher spell slot. For example, a 9th level wizard has a +4 proficiency bonus, so if they cast a 4th level dispel magic, it would be considered to be cast at a 6th level, even though only a 4th level spell slot has been expended.

 

Spellbreaker

There are two new ways for you to prompt concentration saving throws, both of these ways are only prompted by damage dealt by a spell you cast at an equal or greater level than the spell it is attempting to disrupt. First, if you deal damage to a creature with a spell effect on them, that creature must make a concentration check in order to maintain the spell, regardless of if they are the one concentrating on the spell or not. If they fail, the spell ends on them, but only them if there are multiple targets. Secondly, if you attack the original caster directly, you prompt concentration saving throws on spells that do not require concentration, such as mage armor and continual flame. If you attack a creature and should prompt more than one concentration saving throws due to these new abilities, you instead select only one spell to target per instance of damage.

Also, if you prompt a concentration saving throw in the standard way using damage from a spell you cast at an equal or greater level than the spell you are attempting to disrupt, then the DC for this concentration saving throw is equal to the damage you dealt or 13, whichever is higher.