Tempest

Some cunning individuals are unpredictable experts specialize in using alchemical mixtures that wreathe them in frost, flame, or lightning. Fast, chaotic, and possibly mad, they wade into the fight and dare enemies to face the storm.  They create flasks containing chaotic mixtures of the elements themselves, which enhance their abilities to supernatural levels.  They charge into battle recklessly, heedless of any dangers.  The Tempest mantra is "What's the worst that could happen?

Tempests hail from all races and backgrounds.  A tempest can be a noble Human with too much time on their hands, a witty Gnome who is always pushing too far, a curious Elf trying to learn something new during their long lives, a Dwarf hoping to find a new tool to stand against the Drow and the Illithids, a Dragonborn hoping to increase their elemental potency, or virtually any other race with an active streak of curiosity and a reckless disregard for their own safety.

The alignment of a Tempest can vary, but they tend more towards the Chaotic side.  Their alchemical mixtures are bottled chaos after all, and both the creation and usage of these mixtures is very dangerous.  Tempests range the whole spectrum from Good to Evil, but very few of them could be considered lawful.

Bonus Proficiencies

When you choose this archetype at 3rd level, you gain proficiency with the Glassblower's Tools and the Alchemist's Supplies.

Elemental Flasks

Starting at third level, when you finish a long rest you can use your Glassblower's Tools and Alchemist's Supplies to create one each of the following Elemental Flasks.  You can create two of each at level nine and three of each at level seventeen.

Flask of Fire

As a bonus action, you can smash a Flask of Fire against your chest.  This sheathes your body in living flames.  This is dangerous, and if you were careless when creating the flask, it can have unpleasant consequences.  When you smash the flask, roll a d20.  If you roll a 1, you take 1d10 fire damage every turn for the duration.  This damage ignores resistances and immunities.  For 1d4 rounds, you have resistance to fire damage and poison damage, deal an extra 1d6 damage on all weapon attacks, and can activate your sneak attack as long as you do not have disadvantage on the attack roll.  Enemies that hit you in melee must make a strength saving throw equal to 8 + your proficiency bonus + your Intelligence modifier or be knocked back ten feet.

Flask of Frost

As a bonus action, you can smash a Flask of Frost against your chest.  This coats you in an icy skin.  This is dangerous, and if you were careless when creating the flask, it can have unpleasant consequences.  When you smash the flask, roll a d20.  If you roll a 1, you take 3d6 cold damage (this damage ignores resistances and immunities), and, for the duration your speed is reduced to 10 and you can take either an action or a bonus action, not both.  For 1d4 rounds, you have resistance to cold damage and bludgeoning, piercing, and slashing damage from nonmagical attacks, your AC increases by 2, and you have advantage on all Strength and Constitution saving throws and Athletics checks.  Enemies that hit you in melee must make a constitution saving throw equal to 8 + your proficiency bonus + your Intelligence modifier or be restrained until the end of their next turn.

Flask of Lightning

As a bonus action, you can smash a Flask of Lightning against your chest.  This sends you into a heightened state of incredible speed.  This is dangerous, and if you were careless when creating the flask, it can have unpleasant consequences.  When you smash the flask, roll a d20.  If you roll a 1, you take 3d8 lightning damage (this damage ignores resistances and immunities), and you have disadvantage on all Wisdom, Intelligence, and Charisma saving throws for the duration.  For 1d4 rounds, you have resistance to lightning damage and psychic damage,  your walking speed increases by 20 feet, and you can attack twice whenever you take the Attack action.  Enemies that hit you in melee must make an intelligence saving throw equal to 8 + your proficiency bonus + your Intelligence modifier or be stunned until the end of their next turn.  

Flaskmaster

Starting at ninth level, your abilities have grown to the point where you can now create an extra Elemental Flask of each kind whenever you finish a long rest.  Additionally, you gain the maximum benefit from all potions and elixirs.  For example, a Potion of Healing would automatically heal for the maximum amount of 10, instead of requiring you to roll.  Any potion that grants an ability with a duration is doubled.

Ride the Storm

Beginning at thirteenth level, the duration an Elemental Flask lasts is increased by one round if you use another Elemental Flask immediately after the previous one expires.  This effect stacks and maxes out at a total of seven rounds.  Additionally, each elemental flask grants additional bonuses and abilities.

Bitter Chill

Beginning at 13th level, whenever you active a Flask of Frost, you now gain complete immunity to cold damage, and the thick frosty layer distorts your image, making it appear as though there are multiple copies of you.  Enemies that hit you may hit one of these copies instead, as if you were under the effects of the Mirror Image spell.

Stormrage

Beginning at 13th level, whenever you active a Flask of Lightning, you now gain complete immunity to lightning damage, and the electrical energy surging through your body enhances your senses to superhuman levels.  You can see invisible creatures and into the Ethereal Plane, as if you were under the effects of the See Invisibility spell.

Unquenchable Flames

Beginning at 13th level, whenever you active a Flask of Fire, you now gain complete immunity to fire damage, and the swirling flames make you hard to clearly see.  Enemies have disadvantage on attack rolls against you, as if you were under the effects of the Blur spell.

Fury of the Storm

Starting at 17th level, your abilities have grown to the point where you can now create an extra Elemental Flask of each kind whenever you finish a long rest.  Additionally, your Elemental Flasks give you even more benefits when you activate them.

Flaming Chain

Beginning at 17th level, whenever you activate a Flask of Fire, you experience a burst of vigor and energy.  You are cured of all diseases except those caused by an Aboleth, any toxins causing you to suffer from the poisoned condition are burned out of your system, and you are cured of one level of exhaustion.  You can only be cured of one level of exhaustion once per long rest.

Frostbite

Beginning at 17th level, whenever you activate a Flask of Frost, the icy sheen coating your skin drains all the heat from the area.  Creatures that enter this area for the first time or end their turn there must succeed on a Constitution saving throw or take 3d6 cold damage and have their movement speed reduced by 15 feet until the start of their next turn.

Thunderstruck

Beginning at 17th level, whenever you activate a Flask of Lightning, your speed is enhanced to truly superhuman levels.  Your walking speed increases to 100 feet.  If you have a swimming or climbing speed, these are increased by 30 feet.  While enhanced this way, your movement does not provoke opportunity attacks.  Additionally, you have advantage on all melee weapon attacks on creatures that are one size larger than you or smaller.  When this effect ends, a wave of lethargy washes over you, and you gain one level of exhaustion.