Omni Knight to version 7.10 also suffered a decrease in winning rate with only about 51% winrate only. A 3 second cooldown of Purification is a powerful nerf to OmniKnight's midgame. Try to do a single calculation, with a fight in about 30 seconds, if with the old Purification you will buff about 4 times, now you will only buff twice, which makes your team drops to More than 600 HP buffs do not count the damage that this skill can do.
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From @makeline