Psion

Introduced as part of the original roster of 10 characters in 11/13/2013.

Supercharge

 * Active
 * Cost: None
 * Cooldown: 90 Seconds
 * Cast Time: 10 Seconds
 * Increases Psion's energy regeneration by 50 for 25 seconds.

Alterations

 * Overwhelm (5 Hero Points)
 * Increases the duration of Supercharge by 25%.
 * Increases the cost of Supercharge by 50% Health.
 * Crippling Power (5 Hero Points)
 * Decreases the cast time of Supercharge by 30%.
 * Supercharge decreases movement speed by 50%.

Psionic Pulsar

 * Active
 * Cost: 15 Energy
 * Cooldown: None
 * Enhances the Psion's weapon for 5 seconds, increasing splash radius by 0.5. Each use increases attack speed by 10%.

Alterations

 * Preserve (10 Hero Points)
 * Increases the duration of Psionic Pulsar by 50%.
 * Increases the cost of Psionic Pulsar by 2% health.
 * Mega (10 Hero Points)
 * Increases the damage of Psionic Pulsar by 50%.
 * Decreases the attack speed bonus of Psionic Pulsar by 20%

Psionic Blast
This ability is affected by damage upgrades.
 * Active
 * Cost: 30 Energy
 * Cooldown: None
 * Charge Cooldown: 2 Seconds
 * Max Charges: 10
 * Cast Range: 9
 * Deals 80 damage in a radius of 1.

Alterations

 * Classic (10 Hero Points)
 * Removes all cooldown and charges from Psionic Blast.
 * Decreases the damage of Psionic Blast by 50%.
 * Original (10 Hero Points)
 * Reduces the energy cost of Psionic Blast by 50%.
 * Reduces the range of Psionic Blast by 25%.

Power Overwhelming

 * Passive
 * Energy increased by 200 and energy regeneration increased by 2.

Alterations

 * Capacity (10 Hero Points)
 * Increases the maximum energy of Power Overwhelming by 50%.
 * Removes the energy regeneration bonus from Power Overwhelming.
 * Photon Charge (10 Hero Points)
 * Power Overwhelming causes attacks to restore 1 energy.
 * Power Overwhelming decreases maximum health by 30%.
 * Attacks with Psionic Pulsar do not trigger this effect.
 * This health penalty stacks on top of current and future health upgrades.

Psi Drain

 * Active
 * Cost: 5 Energy
 * Cooldown: None
 * Charge Cooldown: 25 Seconds
 * Max Charges: 3
 * Cast Time: 1 Second
 * Drains 2 energy per second for each enemy unit in a radius of 10 for 10 seconds.
 * Up to 3 enemy units can be drained at once.

Alterations

 * Vampire (10 Hero Points)
 * Psi Drain will also restore health.
 * Increases the cast time of Psi Drain by 50%.
 * Gluttony (10 Hero Points)
 * Increases the duration of Psi Drain by 100%.
 * Decreases the radius of Psi Drain by 40%.

Psionic Hold
This ability is affected by damage upgrades.
 * Active
 * Cost: 20% Energy
 * Cooldown: 30 Seconds
 * slows down all enemies in target area of a radius of 6 by 90% for 5 seconds and deals 40 damage.

Alterations

 * Concentrated Hold (10 Hero Points)
 * Increases the duration of Psionic Hold by 100%.
 * Decreases the radius of Psionic Hold by 35%.
 * Crush (10 Hero Points)
 * Increases the damage of Psionic Hold by 100%.
 * Decreases the slow of Psionic Hold by 50%.

Psionic Prison

 * Active
 * Cost: 25 Energy
 * Cooldown: None
 * Cast Range: 6
 * Disables the target unit for 4 seconds and increases damage taken by 5% for 25 seconds.
 * Cannot be used on the same target within 20 seconds.

Alterations

 * Manual (10 Hero Points)
 * Decreases the cost of Psionic Prison by 40%.
 * Decreases the range of Psionic Prison by 85%.
 * Snare (10 Hero Points)
 * Psionic Prison also reduces movement speed by 40%.
 * Adds a 2 second cooldown to Psionic Prison.

Psionic Buster

 * Active
 * Cost: 50 energy
 * Cooldown: 35 Seconds
 * Releases a burst of psionic energy from Psion, knocking away all units, dealing 100 damage, and causing a mini stun.

Alterations

 * Double Buster (10 Hero Points)
 * Psionic Buster will activate a second time after 3 seconds.
 * Decreases the damage of Psionic Buster by 40%
 * Barrier
 * Psionic Buster reduces damage received by 80% for 5 seconds.
 * Increases the cooldown of Psionic Buster by 14%.

Psionic Disabler

 * Active
 * Cost: 90 Energy
 * Cooldown: 45 Seconds
 * Cast Time: 2 Seconds
 * Releases a burst of psionic energy from Psion, dealing 50 damage and causing a 5 second stun in a radius of 10.

Alterations

 * Disturb (10 Hero Points)
 * Increases the stun duration of Psionic Disabler by 20%.
 * Increase the cast time of Psionic Disabler by 50%.
 * Disruption (10 Hero Points)
 * Psionic Disabler cloaks Psion for 10 seconds.
 * Increases the cost of Psionic Disabler by 20% health.

Photon Enhance

 * Passive
 * Decreases the Energy cost of Psionic Blast and Psionic Pulsar by 25%.

Alterations

 * Extend (10 Hero Points)
 * Photon Enhance increases the range of Psionic Pulsar and Psionic Blast by 1.
 * Photon Enhance decreases armor by 2.
 * Endless Energy (10 Hero Points)
 * Photon Enhance increases maximum energy by 300.
 * Photon Enhance decreases damage by 10%.

Psionic Cannon

 * Active
 * Cost: 150 Energy
 * Cooldown: 90 Seconds
 * Cast Range: ?
 * Shoots a charged blast of psionic energy at the targeted unit dealing 600 damage in a radius of 2.

Alterations

 * Duo Cannon (10 Hero Points)
 * Adds a second charge to Psionic Cannon.
 * Decreases the range of Psionic Cannon by 50%.
 * Disintegrate (10 Hero Points)
 * Psionic Cannon deals an additional 50% damage over time.
 * Increases the energy cost of Psionic Cannon by 33%.

Overview
With Supercharge, Psion has the potential to become one of the strongest burst damage casters in the game, soloing early-mid game bosses in mere seconds. Additionally, the small aoe radius of Psion's Q abilities allow her to distribute this damage across groups of enemies when necessary. Psion also has access to stun and slow abilities that make it easier to land other abilities at closer distances, while also pairing well with other stun abilities on the team.

Although Psion's abilities are very powerful, some are locked behind long cast times, especially when factoring in hero alterations, making it dangerous to use these abilities at close range. The (relatively) long cooldowns of abilities such as Supercharge, Psionic Disabler, and Psionic Cannon make it important to use them at the right time, but practice can make timing them easier. Psion cannot move during Psionic Pulsar without losing out on potential damage, and only has range equal to Psion's attack range. Lastly, Psionic Blast's medium-low range combined with Psion's low base health can make her more likely to die than other damage dealing classes.

Pros: Cons:
 * Flexible between strong single target or distributed aoe damage with Supercharge
 * Strong late-game damage options
 * Access to a stun or slow ability
 * Limited range with most abilities
 * Low base health
 * Cannot move while attacking with Psionic Pulsar
 * Long cast times/cooldowns of some abilities
 * Low health regeneration
 * Low movement speed without constant Dash

Build Orders
1) Burst + Rapid Fire Psion - This is arguably the strongest Psion build, and requires as little as 10 Hero Points to be effective.

Q: Psionic Blast +  Classic  (opt. Original)

W: Power Overwhelming + Capacity

E: Psionic Prison / Psionic Hold + Crush (opt. Concentrated Hold)

R: Psionic Disabler (opt. Disturb)

T: Psionic Cannon + Duo Cannon + Disintegrate

Set Details

This set aims to maximize Psion's burst damage potential against bosses and crowds. Psionic Blast is a strong choice that allows Psion to attack while moving and can be spammed easily with Rapid Fire setup. Classic is a versatile perk that allows Psionic Blast to be used without cooldown during Supercharge and is a must have for this build. Original lets Psion get more damage using the same amount of energy, but quick micro is required to compensate for the lower range. Power Overwhelming is used to increase Psion's energy max and allow Psion to bank energy while out of combat to burst down enemies later, without costing minerals. It is also useful for bursting down enemies while Supercharge is on cooldown. Capacity increases this passive ability's effectiveness in allowing Psion to save energy and burst down opponents in a shorter amount of time. Psionic Prison is strongly recommended due to its versatility and support, as well as its ability to be spammed. However, Psionic Hold combined with Crush is an energy efficient ability that can patch up Psion's early-mid game aoe should the team be lacking. Concentrated Hold pairs well with other class' slowing abilities, but is generally inferior to Psionic Prison due to charge up time. Psionic Disabler gives Psion access to aoe damage in a larger radius starting at level 20. On its own, Psionic Cannon gives Psion huge single target burst damage at large range against bosses in late game scenarios when Supercharge is on cooldown. Duo Cannon allows Psion to store up a second charge when fighting bosses may be delayed due to wave timers, and the range decrease is mitigated because Psion will usually fight from mid range. Disintegrate augments Psionic Cannon's damage further.

Items and Upgrades

Because this set usually fights from mid-low range, 2-3 health upgrades are must haves against enemies whose attacks cannot be dodged such as Infested Terran. Costing 700 minerals, the Capacitor is easily charged due to Psion's large energy consumption and pairs with Psionic Disabler to turn Psion into an aoe nuke every 45 seconds. Capacitor also pairs with Psionic Cannon, increasing its already excellent damage by 100%. Damage upgrades scale nicely with Psionic Blast, and allow it to deal more damage to enemies with high armor.

2) Psionic Pulsar Psion - This set aims to patch up many of the first set's weaknesses - low range and lack of sustain - and can be used without significant hero point investment.

Q: Psionic Pulsar + Mega

W: Psi Drain (opt. Gluttony)

E: Psionic Hold + Crush (opt. Concentrated Hold)

R: Psionic Buster / Psionic Disabler (opt. Disturb)

T: Photon Enhance + Extend

Set Details

Psionic Pulsar is this set's main source of damage and allows Psion to deal damage from mid-high range. Mega is used to increase Psion's attack damage under Psionic Pulsar and hit enemies with high armor. Psi Drain essentially grants Psion 6 energy regeneration for 10 seconds if there are 3 enemies in a radius of 10, and is Psion's main way to get energy while Supercharge is on cooldown. Gluttony can be used to double the duration to 20 seconds, as Psionic Pulsar has a large energy consumption, at a cost of decreasing its radius to 6. Psionic Hold + Crush is used to mitigate this set's weakness against groups in the early game, and is energy efficient. Psionic Buster doesn't stop Psion from attacking, but Psionic Disabler is the only ability that complements this set's range. Photon Enhance is used to spam Psionic Pulsar more while Supercharge is on cooldown. Extend increases this set's range by 1, and the armor decrease is negligible, as Psion will likely be fighting from long range.

Items and Upgrades

Extender increases this set's range by 1, making the Psion attack from 8 range while under Focus Fire until level 30. Capacitor is recommended to combo with Psionic Disabler. 1-2 health upgrades rather than 2-3 health upgrades are needed for this set, as it fights from longer range. Cooldown Reduction allows Psion to use Psi Drain and Supercharge more often, effectively increasing Psion's sustained energy regeneration.

Team Synergy
Marine Medic Ghost Reaper SCV Spectre Warhound Cryotech
 * Marine's Calldown: Bunker can provide a safe area to freely use Supercharge and Focus Fire.
 * Marine's Crippling Slash in conjunction with Psion's Psionic Hold can immobilize bosses.
 * Medic's healing abilities mitigates Psion's low health regeneration against enemies whose attacks cannot be dodged such as Infested Terran.
 * Medic's Inject Accelerators gives Psion much needed movement speed and minor energy regeneration when Supercharge is on cooldown.
 * Medic's Caduceus Pulse pairs nicely with Psion's aoe abilities.
 * Psion's Psionic Prison can quickly stun enemies that threaten the Medic such as Hunterlings, Chokers, and bosses.
 * Psion's Psionic Prison and Psionic Disabler's immobilization effects can make it much easier for Ghosts with the Snipe alteration to hit their targets. Additionally, Psionic Prison's zero cast time compliments the low projectile speed of Lockdown, allowing the two to stunlock bosses up to half a minute when timed right.
 * Psion's Psionic Prison's 5% damage increase stacks with EMP Round's 5% damage increase to deal even more damage to bosses.
 * Reaper's Deceleration Field makes it easier for Psion to micro against enemy projectiles since they both fight mid-close range.
 * Reaper's Target's 10% damage increase stacks with Psionic Prison's 5% damage increase.
 * Reaper's Chronos Accelerator can be used with Psion's Psionic Pulsar to bring Psion's attack speed to ridiculous levels.
 * Psion's Psionic Hold pairs nicely with Reaper's U-238 Rounds to immobilize bosses.
 * SCV's buildings give Psion a strong fall back point while Supercharge is on cooldown.
 * SCV's Area Accelerator gives the Psion much needed movement speed, albeit in a short radius.
 * SCV's Calldown: Mule mitigates Psion's low base health regeneration against enemies whose attacks cannot be dodged.
 * Psion's Supercharge allows her to push through waves and kill long range units that threaten SCV's buildings such as Fatties, Swarm Hosts, and Carrions.
 * Psion's Psionic Disabler can neutralize groups of enemies that attack SCV's buildings.
 * Spectre's Territory Cloak gives Psion a safe area to spam abilities against enemies that cannot detect.
 * Spectre's Ultrasonic Pulse softens up enemies (in the absence of Fatties) to be killed easier by Psionic Hold + Crush.
 * Psion's Psionic Prison can stun enemies that threaten Spectre's close range set such as Chokers and Hunterlings. Alternatively, Psion can quickly burst down these enemies with her Q abilities to prevent them from doing too much damage while Spectre is already cloaked.
 * Warhound's Magnetize ability to pull enemies together allows Psion to potentially solo entire waves by nullifying the small aoe radius of her Q abilities.
 * Psion's Psionic Prison's zero cast time gives the Cryotech a precious 3 second window to hit Ice Pillar and accumulate Frozen stacks against bosses with high movement speed such as NT Drone, Prisoner, and Brood Master (enraged).
 * Psion's Psionic Disabler can prevent large groups of enemies from focusing the Cryotech at close range while Cryotech is juggling 3-4 bosses at once.
 * Cryotech's ability to freeze bosses in place for extended periods allow Psion to focus on using Supercharge's duration to its fullest.

Tips

 * Psion's high base energy regeneration essentially makes Dash free. Use Dash frequently to avoid damage, get into position, cancel an ability, or simply move faster.
 * Similarly, the general hero alterations that increase HP by 40 and damage by 2% are strongly recommended, as the increased cost of Dash is mitigated by Psion's large energy regeneration.
 * Using Focus Fire during Psionic Pulsar can freely increase damage, attack speed, and range while preventing loss of potential damage from moving.
 * Psionic Blast can be used while moving, reviving a teammate, and charging Supercharge.
 * Psionic Prison will cancel a teammate's revive in progress.
 * Psionic Blast can hit enemies that are burrowed, cloaked, through fog of war, through Blinding Cloud, and through Dark Swarm.
 * Target fire bosses with Psionic Pulsar and aim in the center of crowds with Psionic Blast to optimize damage.
 * Decreasing the keyboard's repeat delay and increasing keyboard repeat rate can make Rapid Fire abilities fire sooner and more often.
 * With low energy cost, decent range, zero cast time, and zero cooldown, Psionic Prison can be used to prevent teammates from being trapped or instantly killed by enemies such as Hunterlings, Chokers, Infested Ancients, Volatile Infested, and Banelings. Rapid Fire is essential for stunning multiple enemies at once, especially on harder difficulties.
 * With a low energy cost and decent knockback, Psionic Buster can be used as an emergency escape tool against enemies in close proximity such as Infested Ancients, Tunnelings, Hunterlings, and Chargers.