Andromeda’s Magic Tether

When a spell caster you can see starts casting a spell within range, you release a magical siphon, tethering the caster to you for a brief moment. If the target spell caster was casting any spell of 5th level or lower, the spell is consumed by the tether and the spell does not take effect.

For each spell of 5th level or higher cast by the target, make a contested ability check using your spellcasting ability. The target spellcaster does the same as a magical battle of willpower occurs. If you were the sole target of the target spell casters spell, then you have advantage on this roll. On a successful check, the spell is consumed by the magical tether and does not take effect.

If you fail your contested check, the tether is overpowered and the target caster’s spell is cast as normal and the target caster regains a spell slot of third level or lower.

If you successfully negate the target spell with your own, you also regain a spell slot. The slot restored is 4 spell levels lower than the spell cast by the target (minimum 1st level spell slot recovered). This cannot restore spell slots greater than your maximum for that level, and does not grant you access to spell levels you are not able to cast yourself. If you have all of your spell slots for that level, then you regain a spell slot of a lower level. If you have all lower level spell slots available, then you gain advantage on your next spell attack and a wild magic surge occurs, roll on the magic surge table.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the tether increases in power with a roll needed for any spells cast by the target above the level this spell is cast at. (Ex. Cast at 6th level, rolls required for spells cast by the target 7th level and up)