Teamfight Tactics' patch notes for July 1 have been revealed by Riot developer August Browning and retweeted by Teamfight Tactics Product Lead Richard Henkel. There's no official blog post yet, outside of the Teamfight Tactics tournament announcement, but these sources are as official as they come.

We're looking at two major types of balance changes this patch: tweaks to specific champions and changes to the chances of getting different tiers of champions based on your level.

Elise, Poppy, Varus, Veigar, Miss Fortune, and Karthus are all getting pretty substantial buffs, as their ultimates will cost less mana to cast.
Kennen and Volibear are both getting improved attack speed.
Veigar's ultimate will deal 50 more damage at level 2 and 100 more damage at level 3.

The goal of the tier scaling at different levels is to improve the viability of rushing 2 and 3 star tier 2 units, which are currently much riskier to go for than 3 star tier 1 units.

Cover Image Courtesy of Riot Games.