Martial Magician

Some wizards were born to study in dusty libraries amongst yellowed pages and wrinkled scholars. Other wizards travel the world and the planes beyond, seeking never-before seen creatures and magics far removed from the comforts of civilisation. And some wizards prefer to take their lessons from an even more unlikely place - the battlefield.

These wizards are Martial Magicians. The kith and kin who study this practise wield mundane weapons as readily as gladiators, using the rush of combat to push their spellcasting to edge of their abilities. Martial Magicians are taught to lend their intellect to their defence, weaving through dangers with protective enchantments before retaliating with unerring accuracy.

Editor's Notes - This was mostly an experiment to create another melee / spell caster sub-class option for the Wizard, much like the Bladesinger sub-class from the Sword Coast Adventurers guide. The Bladesinger I think is (mostly) fine in terms of balance, but when you stack the extra attack and AC bonuses from Haste with the extra attack and AC bonuses from the Bladesong, the sub-class starts to out-do more traditional combat focused classes without too much downside. Hence this home-brew, please enjoy at your leisure!

Bonus Proficiencies

When you select this school at 2nd level, you gain proficiency with simple, and martial weapons.

Unarmored Defence

At 2nd level, while you are wearing no armour and are not wielding a shield, your AC equals 10 + Dexterity modifier + your Intelligence modifier.

Editor's Notes - Not much in these level 2 sub-class features, I just wanted to hand out some weapon proficiencies and an acceptable AC so that the Wizard can start hitting things without getting hit. Unarmored defence doesn't add much more than what Mage Armor gets you, but it at least means that you don't have to leave home with Mage Armor and Shield in your book just to stay alive.

Reflexive Casting

At 6th level, you add the haste spell to your spellbook, if it is not there already. In addition, you can cast haste using your reaction when you roll initiative. When you cast haste this way you may target only yourself.

Once you use this feature you cannot use it again until you finish a short or a long rest.

Editor's Notes - Now we're cooking. Haste is basically a one stop shop for all your combat needs. +2 to AC, an extra attack, double your movement and advantage on dexterity saving throws? At this point it would be stupid to give the Wizard any extra help whacking creatures with their weapons, so instead I reckon we just make it easier to start the party. Having said that, using your reaction to cast spells that should take an action is somewhat akin to getting two actions a turn, so slapping a short rest limitation on this feature is hopefully enough to keep things on a low boil.

Heightened Focus

Starting at 10th level, you may use a bonus action on your turn to enter a state of heightened focus. For the next minute your attack rolls critically hit on a roll of 19 or 20. This benefit is only granted to you while you are using your concentration to maintain the effects of a spell.

Once you use this feature you may not use it again until you finish a long rest.

Editor's Notes - So rolling critical hits always feels great, but in the grand scheme of things critical hits don't add much to your total damage per round output. There are some shenanigans you can pull with Elven Accuracy (Xanthar's Guide to Everything), but even then I wouldn't consider this feature as too much of a game changer for the Wizard. Even so, this is playtest material, so lets hedge our bets and throw a long rest and a short duration and a tricksy concentration pre-condition in there to keep things cool.

Effortless Concentration

Starting at 14th level, whenever you cast haste, you do not need to use your concentration to maintain its effect. The spell instead lasts for its duration, regardless of any subsequent spells you cast.

Editor's Notes - Here we go, the big cheese. I've always thought the level 14 features of the Wizard sub-classes in the Player's Handbook were the bomb. Overchannel, Master Transmuter - these features really hit the deck like a tonne of bricks. Our feature here helps us keep our Wizards hitting creatures with their weapons, which is all we want to do. The synergy between Reflexive Casting and this feature basically ensures our Wizard always has the benefits granted by Haste at zero cost. Seems more than strong enough as a capstone feature.