Overcome with rage, Valkyr unleashes a pair of energy claws and becomes immune to all damage and status effects. Normal attacks deal 100 / 125 / 200 / 250 base damage within 2 meters. Wall attacks and slide attacks inflict 300 / 375 / 600 / 750 base damage for each strike. Aerial attacks inflict 200 / 250 / 400 / 500 base damage, and slam attacks inflict 300 base damage within 5 meters. Attacks have a 200% critical damage multiplier with a 50% critical chance and a 10% status chance. Additionally, Valkyr is healed for 1% / 2% / 4% / 5% of the total melee damage she inflicts. Base damage is distributed evenly between Impact b Impact, Puncture b Puncture, and Slash b Slash. Base damage is affected by Power Strength and the Melee Combo Counter, while the lifesteal is not. Hysteria is also affected by equipped melee mods including: Base damage (e.g., Steel Charge), elemental damage, physical damage, faction damage, channeling (e.g., Life Strike), critical damage, critical chance, status chance, attack speed (e.g., Berserker), and range mods. Hysteria's base damage uses the following expression when accounting for Power Strength: Modified Base Damage = Base Damage × (1 + Base Damage Bonus) × (1 + Power Strength). As an example, with a maxed Steel Charge, Pressure Point, and Intensify, the normal attacks of a rank-3 Hysteria will have 250 × 2.8 × 1.3 = 910 base damage. Range mods do not affect the radius of slam attacks. Hysteria is not affected by the equipped melee weapon's stats, weapon augments (e.g., Justice Blades), class-specific mods (e.g., Covert Lethality), or stat-modifying skins (e.g., Manticore). Radial damage from slam attacks diminishes with distance, does not have a critical chance, is not affected by the Melee Combo Counter, and will cause enemies within range to suffer a knockdown. Ground finishers inflict 1600% of the total modified damage from normal attacks. Prompted melee finishers inflict 6400% of the total modified damage from normal attacks as Finisher damage. The damage composition of a ground finisher is the same as a modified normal attack; however, Impact b Impact damage from ground finishers is multiplied by 125%. The finisher multipliers for both attacks are affected by Finishing Touch. Each attack adds to the Melee Combo Counter; however, radial damage from slam attacks does not. Hysteria's innate lifesteal is calculated from the total damage of Valkyr's melee attacks after resistances are applied. Hysteria's lifesteal is also additive when combined with other sources of lifesteal (e.g., a maxed Life Strike and a rank-3 Hysteria will yield 0.2 + 0.05 = 25% lifesteal on channeled hits). Status immunity includes crowd-controlling effects such as knockdowns, staggers, and Nauseous Crawler paralysis. Certain attacks will still push Valkyr away, and shock waves will cause her to bounce into the air. However, these attacks will not force Valkyr to the ground. Statuses that were already active when Hysteria was cast will not be removed. However, Valkyr will be immune to their damage regardless. Valkyr is not immune to Commander teleportation, Regulator minimap disruption, Cryofloors, Tar-Mutalist MOA slows, or Swarm-Mutalist MOA screen hazing. While Hysteria is active, its claws are the only weapon Valkyr can use. However, her other powers can still be cast normally. Valkyr emits an aura with a radius of 5 meters around her while Hysteria is active, and 30% of the total damage she ignores is stored. If any enemies within this aura have line-of-sight of Valkyr when Hysteria is deactivated, Valkyr will be dealt 25% of all stored damage as Impact b Impact damage. The aura will continue to grow up to 20 meters and each kill reduces it by 1 meter. It cannot be reduced below 5 meters under any circumstances. Damage percentages are not affected by Power Strength. Aura radius is not affected by Power Range. Stored damage is calculated from the total damage Valkyr ignores before resistances are applied. The amount of stored damage can be monitored at the top right of the HUD under Hysteria's ability icon. Highlighted enemies become unmarked if Valkyr moves out of range, negating the damage taken when Hysteria expires. Since enemies need line-of-sight, invisibility prevents the damage. Hysteria consumes 2.5 energy per second and the cost will increase over time, up to 15 energy per second, while active. It will remain active until either Valkyr's energy is depleted, or the ability is deactivated by casting it again (default 4). Activation energy cost is affected by Power Efficiency, and the energy drain is affected by Power Efficiency and Power Duration. Valkyr cannot replenish energy using Team Energy Restores, Energy Siphon, or Trinity's Energy Vampire while Hysteria is active. However, collecting Energy Orbs will still replenish energy normally. Hysteria comes installed with its own unique stance. Additional combos will be unlocked as Hysteria increases in rank. Has a cast time of 1 second, affected by Natural Talent. Despite being classified as its own weapon, Speed Holster will have no effect on casting speed. However, it will affect Hysteria's 'unequip' animation, played upon its deactivation.

Just a copy-paste from the wiki.