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Guard allies within 175 units of you, and allies you target with spells for 2.5 seconds. While Guarding, if you or the ally take damage, both of you gain a shield for 70 - 150 (+25% of the Guardian's Ability Power) (+12% of the Guardian's Bonus Health) and receive 20% bonus movement speed for 1.5 seconds.
70 - 40 seconds Cooldown (based on level). Guardian only goes on cooldown when the shield is triggered.
Cooldown increased at early levels, decreased at late levels. Shield base value and ratios increased.
Guardian is the newest in "hidden power" mechanics: Like Bond of Stone or Aegis of the Legion's old aura, players are getting a lot of power from it, but they often don't feel it. We want to make Guardian a little weaker (it's overperforming), but also more noticeable (it's underappreciated).
COOLDOWN :  ⇒ 70-40 (at level 1-18)
BASE SHIELD : [60-150] ⇒ 70-150 (at level 1-18)
SHIELD AP RATIO : [0.20] ⇒ 0.25 ability power
SHIELD HEALTH RATIO : [10%] ⇒ 12% bonus health
DEFINITELY NOT BRAUM Guard allies within 175 units of you and allies you target with spells for 2.5 seconds. While Guarding, if you or the ally take damage, both of you gain a shield and activate haste for 1.5 seconds.
COOLDOWN 45 seconds
SHIELD 60 - 150 +(0.20 AP) + (+10% bonus health)
HASTE +20% Movement Speed