This Monk subclass, like Eldritch Knight or Arcane Trickster, is a 3rd caster. Spell slots and the ability to use cantrips as a bonus action reduce the required Ki consumption of this Monk. It is intentional that this monk can cast a spell and a cantrip or 2 cantrips in a turn, maintaining damage output while being able to focus more on Wisdom than Dexterity. 

Spellcasting

When you reach 3rd level, you augment your martial prowess with the ability to cast spells. See Spells Rules for the general rules of spellcasting and the Spells Listing for the wizard spell list. To cast one of these spells, you use its casting time and other rules, but you don’t need to provide material components for it.

Cantrips

You learn two cantrips of your choice from the wizard spell list. You learn an additional wizard cantrip of your choice at 10th level.

Spell Slots

The Way of the Elements Spellcasting table shows how many spell slots you have to cast your wizard spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell’s level or higher. You regain all expended spell slots when you finish a long rest.

For example, if you know the 1st-level spell shield and have a 1st-level and a 2nd-level spell slot available, you can cast shield using either slot.

Spells Known of 1st-Level and Higher

You know three 1st-level wizard spells of your choice, two of which you must choose from the transmutation and necromancy spells on the wizard spell list.

The Spells Known column of the Way of the Elements Spellcasting table shows when you learn more wizard spells of 1st level or higher. Each of these spells must be a transmutation or necromancy spell of your choice, and must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one new spell of 1st or 2nd level.

The spells you learn at 8th, 14th, and 20th level can come from any school of magic.

Whenever you gain a level in this class, you can replace one of the wizard spells you know with another spell of your choice from the wizard spell list. The new spell must be of a level for which you have spell slots, and it must be a transmutation or necromancy spell, unless you’re replacing the spell you gained at 3rd, 8th, 14th, or 20th level from any school of magic.

Spellcasting Ability

Wisdom is your spellcasting ability for your wizard spells, since you learn your spells through study and meditation. You use your Wisdom whenever a spell refers to your spellcasting ability. In addition, you use your Wisdom modifier when setting the saving throw DC for a wizard spell you cast and when making an attack roll with one.

Spell save DC = 8 + your proficiency bonus + your Wisdom modifier

Spell attack modifier = your proficiency bonus + your Wisdom modifier

Way of the Elements Spellcasting

MONK LEVEL	CANTRIPS KNOWN	SPELLS KNOWN	— SPELL SLOTS PER SPELL LEVEL —
			1ST	2ND	3RD	4TH
3rd	2	3	2	—	—	—
4th	2	4	3	—	—	—
5th	2	4	3	—	—	—
6th	2	4	3	—	—	—
7th	2	5	4	2	—	—
8th	2	6	4	2	—	—
9th	2	6	4	2	—	—
10th	3	7	4	3	—	—
11th	3	8	4	3	—	—
12th	3	8	4	3	—	—
13th	3	9	4	3	2	—
14th	3	10	4	3	2	—
15th	3	10	4	3	2	—
16th	3	11	4	3	3	—
17th	3	11	4	3	3	—
18th	3	11	4	3	3	—
19th	3	12	4	3	3	1
20th	3	13	4	3	3	1

Elemental Weave

Starting at 3rd level, you may cast cantrips with a casting time of 1 action as a bonus action. 

When you use your Action to cast a spell or cantrip you may use your Martial Arts or Flurry of Blows features.

Deflect Spell

Starting at 6th level, you can use your reaction to deflect magical energy when you are hit by a ranged spell attack. When you do so, the damage you take from the attack is reduced by 1d10 + your Wisdom modifier + your monk level.

If you reduce the damage to 0, you can redirect the spell if you have at least one hand free. If you redirect the spell in this way, you can spend 1 ki point to make a ranged spell attack as part of the same reaction. You make this attack with proficiency and it has a range of 60 feet. On a hit, the target takes 1d10 damage of the spell's original damage type.

This spell's damage increases by 1d10 when you reach 5th level (2d10), 11th level (3d10), and 17th level (4d10)

Potent Spellcasting

Starting at 11th level, you add your Wisdom modifier to the damage you deal with any wizard cantrip.

Elemental Awakening

Starting at 17th level, you can cast Investiture of Flame, Investiture of Ice, Investiture of wind, or Investiture of stone once without spending a spell slot. You can use this feature again when you complete a long rest.