Teamfight Tactics is in a strange, pre-rotation state at the moment. While the gameplay itself is in a pretty good state and the meta generally is pretty diverse, most TFT players are just waiting for the arrival of Set 3 mid-March: TFT Galaxies. The balance team isn't sitting pretty, however, and decided that a small tweak to Shadows was needed to reduce their overall strength.
In patch 10.4b, the first B-patch in weeks, reduces the overall Shadow Bonus Damage even further after it was already brought down in patch 10.3. Instead of units receiving a 165% damage buff, they'll now be boosted by 'just' 150%.
Two Shadow champions are targeted specifically too. While Sion's Spell Damage at level one remains the same, his upgraded versions will deal slightly less damage. A level two Sion's Decimating Smash deals 350 damage instead of 400, while a level three Sion's damage is reduced from 800 to 700. The opposite goes for Master Yi, who sees his early damage toned down. His Bonus Damage at level one is reduced drastically, from 75 to 40, while at level two the bonus is brought down from 100 to 80.
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