School of the Iron Mind

The school of the Iron Mind focuses on mental exercises and maintaining focus under pressure. Adepts of this school are known to be able to withstand a significant amount of physical and mental stress without breaking or losing concentration.

Mind Over Body

Starting at 2nd level, you can make an Intelligence saving throw to maintain concentration on a spell instead of Constitution.

Spell Extension

Starting at 2nd level, whenever you cast a spell that does not require concentration, you can choose to concentrate on that spell. While concentrating on that spell on subsequent turns, whenever you cast that spell again you can treat it as if you had spent a spell slot 1 level higher than you did. You lose this benefit if you lose concentration on the spell.
Ex. When you cast and choose to concentrate on a Fireball spell and then cast it again on your next turn using a 4th level slot, it deals damage as if you had cast it at 5th level. If you cast fireball at 6th level while using this feature, you can treat it as a 7th level fireball.

Iron Focus

At 6th level, you have learned to block out external stimuli and focus on your arcane casting. When you cast a spell that requires concentration while already maintaining concentration on a another spell, you can channel extra energy to maintain both spells. Maintaining concentration on multiple spells drains your energy. If the combined level of the two spells exceeds 5th level, you must expend a spell slot equal to the difference or higher on each turn or lose concentration on the higher level spell (in case of a tie, you choose which spell to keep). Concentration checks are made separately for each spell.

Force of Will

Starting at 10th level, whenever you begin dual concentration with Iron Focus, you can choose to generate a mystical shield of force around you. You gain temporary hit points equal to your Wizard level, and on subsequent turns when you maintain the concentration on at least two spells you regain those temporary hit points up to half your wizard level. Concentrating on less than two spells at any point causes the temporary hitpoints to stop regenerating until you begin Iron Focus concentration again, and losing concentration on all spells completely removes temporary hitpoints gained from this feature. You can only activate this feature per short rest.

Arcane Multitasking

Starting at 14th level you can concentrate on as many spells as you want with Iron Focus, spending spell slots for the combined difference as normal.