I've had this idea before way back when and I hope no one remembers
Tempest Knight (AKA Tempest Mage or simply Tempest, shortened to temp)
While attempting to understand the nature of the ember, the tempest society, a forgotten sect of the embermage have unlocked more horror than they could have imagined. A horrible experiment occurred, timed correctly with the rising of a great evil. All of the members of the tempest society were sucked into another dimension never to be heard from again. To avoid panic, scrutiny, and most importantly, investigation, the empire has simply dismissed that the tempest society has never existed at all.
The dimension was harsh and unforgiving, given only time, darkness, enemy eyes among them, they had no choice. To survive, they had to break the covenants they held restricted, and delved deep into the secrets of the ember; cracks of lightning were first to come, allowing the magi to create fires to help them see into the harsh new world; they developed methods to hasten their own speed and slow their opponents that they may escape their predators; finally they found ways to harness the crystals for potent use, ripping their enemies apart instead of simply running in fear of them. This was progress, and though they were visibly corrupted by the ember to do so, it was another victory for life.
The dying cry of a beast named Ordrak deep within the mines of a boomtown has created rifts in time across the land. One of these places was within the now derelict towers belonging to the tempest society. Flung open from their grim prison in a fate akin to hell; the tempest society had to work to survive and gained truer understandings of the nature of ember than they though possible before.
Though welcomed back into the very empire that at one time dismissed them, they were viewed as outsiders. The dead, or at least, those that should have been. Half of the tempests cleaved from the empire, insulted and demanding reparations and working toward revenge. However, and oddly, the more ember-corrupt sided with the empire to foster a new school into tempestry.
Tempest Tree - The tempest can alter the very fabric of time to his own bidding, allowing him to change, predict, and alter what is to occur.
Slow - When used on an enemy, they attack and move 50% slower for X seconds. X is 10 seconds, +2.5 seconds per level.
Zone of Stasis (requires level 5 slow) - When used, creates a X wide bubble of slowing distortion, slowing enemy movement and attack speed by 15% for 30s. X is 5 feet(small radius), +1 foot per level.
Stop! (requires lev 5 slow) - When used, target creature is stopped for X seconds (cap of 3 secs for PVP) X is 1.5 seconds, +.75 seconds per level.
Reversal of Fortune - Revives an ally with X health and Y mana. X is 10% of their max health + caster's energy contribution. +2.5% per level. Y is 10% of their max mana + caster's energy contribution. +2.5% per level.
Time buffer - Causes a bubble of compressed time around the target which reduces all damage dealt by X% for 10 seconds. X is 10%, +5% per level.
Return Fire - PASSIVE - lasts 30s, any missile projectiles fired at you has a X% chance to be stopped and returned to attacker. X is 30%, +3% per level.
Time Warp - Cause a rift in time allowing the player apparently instantaneous transmission, in layman's terms: he teleports X feet in front of him. X is 10 feet, +3 feet per level.
Haste - For X seconds, all party members move and attack 50% faster. This ability refreshes by 5s for each enemy killed while under the effect of this skill(max X seconds). X is 10s, +1s per level.
Zone of Disturbance - Causes a frictive zone around target with concentric rings of hastened and dilated time to rip targets in the zone apart. X% of DPS. X is 85%, +10% per level.
Double Magic - The next 3 spells cast by caster will cost normal, but fire twice instead of once.
Storm Tree - The tempest can use his power of time and dimension to create devastating weather at his command.
Wind Buffet - 15 foot knockback with X% DPS. X is 15, +3% per level.
Slicing Wind - The tempest fires X sickles of concentrated wind to cut through enemies in a straight line (max distance is off the screen), sickles deal Y% DPS. X is 3; +1 every even level. Y is 10%, +5% per level.
Cyclone - Create a X wide funnel of pure destructive energies that follows cursor and deals Y% DPS. Constantly drains mana. X is 5, +1 per level. Y is 30%, +15% per level.
Storm - Create a storm for 20s which deals X% DPS lightning damage to all enemies in storm and has a small chance to stun them for 3 seconds. X is 10%, +5% per level.
Wind Armor - Requires Lev 5 wind buffet, Lasts X hit(s), enemies that hit the caster will suffer 15 foot knockback. X is 1, +1 per level.
Lightning Armor - Requires Level 5 storm, Lasts X seconds, enemies that strike caster take Y% DPS. X is 30, +5 per level. Y is 10%, +5% per level.
Thunderbolt - Strike an enemy with a piercing blast of lightning dealing X% DPS before chaining to adjacent enemies for 1/2 damage. X is 115%, +20% per level.
Curse of Lightning - Causes target to run away in fear of the curse, after 5 seconds, target is struck by lightning dealing X% DPS. X is 250%, +45% per level.
Dancing Fury - Requires Slicing Wind rank 5 and Lightning Armor rank 3 - Release a fan of powerful wind sickles in all directions dealing sickle damage. Increased levels in dancing fury reduce skill cost.
Supercharge - Supercharges an enemy with electricity. When they die, X bolts of powerful lightning will be released, attacking the nearest enemy. Bolt damage is Y% DPS. X is 5, +1 per odd level. Y is 35%, +10% per level.
Gravity Tree - The tempest can take hold of the very fabric of the world, creating and destroying and changing the laws of the world.
Gravity Well - Sucks all enemies into the well dealing X% DPS per second for 5 seconds. X is 10%, +5% per level.
Ragdoll - The tempest grabs all enemies within X feet, lifts them high into the air before slamming them back into the ground dealing Y% DPS. X is .5 feet, +.5 feet per level. Y is 80%, +12% per level. (This skill is intended to be initially single target, but eventually obtain AoE effectiveness.)
Crush - Slam enemies into the ground with tremendous force. While crushed, they cannot move and take X% DPS. X is 50%, +10% per level.
Summon Ember - Summons dozens of shards of ember to pierce the target(s) before they crack and shatter. X% DPS initial. Y% DPS to area on shatter. X is 92%, +6% per level. Y is 46%, +5% per level.
Unsummon - Create a X foot radius portal under enemies with a 25% chance to instantly kill them. X is 2, +.5 per level.
Portal - create a portal, portals are inactive until a sibling portal is placed. Portals may only be placed on the same map and last for X seconds. X is 300, +15 per level.
Multiplicity - create a copy of yourself to aid in escape, the tempest can also trade places with copy while it's onscreen. Copy has X health. X is 10% of player health +10. +2.5% health per level. Copy can run and move, but cannot attack.
Gravity Trap - create a rift of energy below caster's feet that explodes when an enemy steps on it. It deals X% DPS. X is 50%, +8% per level.
Swap - Requires multiplicity lev 5. Swap positions with target creature. Each level reduces cost.
Identity Crisis - Polymorph target enemy to appear like you. Other enemies will also view polymorphed creature as you. Polymorph lasts X seconds. X is 3, +1 per level. (This one is fun, imagine a huge crowd that you can turn against itself).
Making a to-do list is on my to-do list.