If the trait’s passive is maximized, the following traits will hold top power in Teamfight Tactics Season 3.
4 Spies

With the highest passive, Spy champions receive up to 80% attack speed for the first 6 seconds of combat, refreshing whenever a kill is secured. With that additional attack speed, Spy champions will obliterate the low-health enemy backline, with targets sometimes being taken down before they can even cast a skill. Additionally, Spy champions jumping out will evade many enemy skills, forcing opponents to use their abilities on your tanks.
Since Spies already deal significant damage, the perfect complement to this composition would be the tankiness provided by Garen (merged from 3 Pilots). The champions Karma and Lux will activate the Shadow and Mage passives to strengthen the team further.
6 Rebels

This is one of the most popular compositions in Teamfight Tactics Season 3. The reason is that it has too many advantages, being strong in both the early and late game, with multiple carries allowing you to choose the right carry based on the items you obtain.
In the early game, Rebels can outperform other traits thanks to the damage and shield from their passive. In the mid-game, you can choose various main carries for a diverse team from Master Yi (attack speed items) or Yasuo, and later easily transfer items to Kayle or Jinx.
By the late game, you can stack items on Aurelion Sol and position him at the center of the 6 Rebels, allowing him to fly across the map unleashing skills with immense shields and damage.
6 Time Mages

With 6 Time Mages, the entire team gains 65% attack speed every 4 seconds, allowing you to pair with any carry champion. If using Jhin, you should utilize items like Infinity Edge, Guinsoo’s Rageblade, and Bloodthirster.
Regarding the Time Mages champions, all will primarily serve as tanks; the most impressive strength of this composition is that Thresh will continuously pull champions from the bench to buy time for Jhin to unleash shots. The more champions Thresh pulls, the longer he buys time, allowing Jhin to gain more attack speed and become even more powerful; he can still carry without needing Shadows.
4 Pirates

The strength of Pirates lies not only in the amount of damage or tankiness but their unique power to gain unlimited strength during the match. Specifically, with the 4 Pirates passive, each kill made by Pirate champions has a chance to yield 1 gold or a small item, making it unsurprising for a Pirate composition to end up with 15 or 20 large items in a match.
On the other hand, Pirates can combine with many compositions, so they are not restricted to any particular champion. You can combine Pirates with Mages, allowing Gangplank to become fully tanky while still being able to wipe out the entire enemy team with one skill. You can also play Pirates alongside Garen (3 Pilots); while the enemy team is busy attacking Garen, Darius can continuously cleave down low-health enemies.
6 Super Tech

In this composition, the main sources of damage will be focused on Irelia, Kayle, and Ekko. Irelia will deal physical damage with her “perfectly aimed” thrusts at her target. Notably, if Irelia’s skill secures a kill, she will immediately thrust at the target with the highest mana. If she doesn’t secure a kill, she can use her skill with just 30 mana, allowing her to thrust again in an instant if she activates the Bladesman attack.
Accompanying Irelia will be Vi, who uses her skill to dash to the farthest enemy champions; these are two incredible machines hunting down enemy carries of Super Tech. Next, Kayle will serve as the main magic damage dealer, while Ekko will deal damage and create effects across the map.