The most significant changes brought in by the TFT Patch 9.15 affects Void and Assassins. Void units now inflict true damage if their bonus is active, which should give them a major boost, considering their usual low damage. Assassins will move faster than ever, but they can also be targeted earlier. Non-Assassin units will move post-patch, making the back lines less likely to open-up for Assassins to enter.
Knights also evolved in the 9.15 Patch and now help your team ignore 15/30/55 damage from all sources now, instead of solely blocking basic attack damage.
Another large-scale change this patch is coming to the way streaks work in Teamfight Tactics.
Pre-patch, going on an early game win-streak was a way to put yourself in a good place, while trying to collect gold early from a loss streak could be a dangerous proposition.
Both kinds of streaks start earlier now, which will likely assist both sides.
They should now be considerably more even, thanks in part to the nerf to player damage that also came in.
This nerf means losing just a few rounds will not be a instant death sentence.
Knights in Teamfight Tactics Patch 9.15:
The biggest change brought by Patch 9.15 is the buff Knights received.
Rather than only blocking a small portion of basic attack damage that hit themselves, Knights can now provide a defensive boost to the whole team.
This means just four Knights can now block 30 damage from every ability and attack any enemy uses.
Knights additionally received fairly significant armour buff across the board.
Assassins in Teamfight Tactics Patch 9.15:
Assassins now have a few more specifics around the way they interact with the game, including moving faster than other units, and jumping earlier.
Consequently by the time Assassins jump, the other team may not have moved much, making positioning against Assassins more important.
As a slight bonus for this change, and the nerf they suffered last patch, some of TFT’s Assassins received changes to their abilities, including buffs to Rengar, Katarina, and Evelynn.
Streak changes in Teamfight Tactics Patch 9.15:
Both win and loss streaks received identical adjustments in Patch 9.15.
Rather than their old breaking point, the needed amounts of both wins and losses decreased, making them both more effective.
The new win/Loss streak breakpoints for both streaks is: 2/5/8 – 2/4/7
Damage in Teamfight Tactics Patch 9.15:
Damage in the pre-patch game has always been a little high.
TFT developer Riot is attempting to scale-back player damage, but without any specific ideas about how to achieve that.
Damage for certain tiers of units and certain star levels has now changed, making it easier to just list them out.
Damage from Spiderlings/Elemental Golem: 2 – 1
Tier 4 (1 Star): 3 – 2
Tier 5 (1 Star): 4 – 3
Tier 3 (2 Star): 4 – 3
Tier 4 (2 Star): 5 – 4
Tier 5 (2 Star): 6 – 5
Tier 4 (3 Star): 7 – 6