(Innate): Every 40 points of bonus health grants Vladimir 1 ability power and every 1 point of ability power grants Vladimir 1.4 bonus health. These bonuses do not stack with themselves.
Crimson Pact is a passive ability with 2 separate effects, granting Vladimir an amount of bonus health dependent on his total ability power and bonus ability power dependent on his bonus health.
While specifically noted that Crimson Pact will not stack with itself, any ability power gained through Crimson Pact will be affected by Rabadon's Deathcap. The ability power added in this way will be converted into health through Crimson Pact. You need to gain approximately 74 bonus health to be granted 1 additional health this way. See here for reference. With pure % health runes the bonus health needed will be 61.
(Active): Vladimir drains the lifeforce of his target, dealing magic damage and healing himself.
If Vladimir uses Sanguine Pool immediately after Transfusion, the healing projectile is disjointed and Vladimir will not be healed.
(Active): Vladimir sinks into a pool of blood becoming untargetable for 2 seconds and slowing enemies above him by 40% for 1 second. Additionally, he deals magic damage every half second to them and heals himself for 12.5% of the damage done.
Cost: 20% of current health
Diameter of AoE: 300
Cooldown: 26 / 23 / 20 / 17 / 14 seconds
Magic Damage Per Half-Second: 20 / 33.75 / 47.5 / 61.25 / 75 (+3.75% of bonus health)
Maximum Magic Damage: 80 / 135 / 190 / 245 / 300 (+15% of bonus health)
One exception is Quicksilver Sash, which can be activated while using Sanguine Pool.
Even though not stated in the tooltip, Sanguine Pool also gives Vladimir a 37.5% movement speed boost for 1 second upon activating the ability.
Some abilities such as 科'加斯的Feral Scream and 卡西奥佩娅的Petrifying Gaze can still affect Vladimir as he enters Sanguine Pool. He will take damage and crowd control effects, but Sanguine Pool will still take effect regardless.
When in Sanguine Pool, Vladimir is still stunned when passing through 维迦的Event HorizonEvent Horizon. If he does this, he will remain in his pool for its duration and remain stunned when coming out if the stun has not expired.
Tides of Blood
(Active): Vladimir unleashes a torrent of blood dealing magic damage to all nearby enemies. Each cast of Tides of Blood gives him an Empowered stack, which increases his healing and regeneration by 8%, and causing his next Tides of Blood to deal 25% more damage but cost 25% more health. This lasts for 10 seconds, and stacks up to four times.
Maximum Magic Damage: 120 / 170 / 220 / 270 / 320 (+0.45 per ability power)
Tides of Blood is a point blank area of effect ability that sends out projectiles of blood at all enemy units in a radius around Vladimir, dealing magic damage on impact. Upon cast Vladimir also gains a stacking 'Empowered' buff for 10 seconds that increases the effectiveness of healing and regeneration upon himself, and increases the base damage and health cost of subsequent Tides of Blood casts.
The Empowered buff does not affect bonus ability power damage on Tides of Blood in any way.
(Active): Vladimir infects all enemies in the target area with a virulent plague which increases the damage they take from all sources by 12% for 5 seconds. After these 5 seconds, infected enemies take magic damage.
Hemoplague is a ground targeted area of effect ability that debuffs enemy units in the target location for 5 seconds. Debuffed units have all incoming damage amplified, and upon debuff expiration they take magic damage.