Arcane Architect

A master of the control, your spells have a potency that can turn any situation in your favor. You gain the following benefits:

• You have a pool of Arcane energy equal to your proficiency modifier that recharges on a long or short rest, you may expend a use from this pool to do one of the following:
• Whenever a creature or creatures succeeds a saving throw against a spell you cast you can expend a spell slot of the same level as a reaction and the creature(s) must remake the save. If the creature succeeds from a use of legendary resistance this feature can not be used to force the creature to reroll its save.
• When you miss with an attack roll on a spell you may immediately reroll the attack (expending appropriate spell slot) and potentially hit the attack.
• When you lose concentration on a spell you may as a reaction spend a spell slot equal to the spell you are concentrating on to continue maintaining the concentration on the spell.