Choose a Legend Before the Match
This can be considered the biggest change in Teamfight Tactics Season 9 compared to previous seasons. Essentially, Legends will allow players to know in advance which Tech Cores they will definitely receive when entering the match. This helps players to clearly define their play style even before the game begins.

Of course, players can still choose other Tech Cores for the match. Therefore, players need to be very mindful when selecting a Legend as well as Tech Cores when entering the match in Season 9.
No More First Common Selection Round
In Season 9, players will start by voting for 1 of 3 random areas with unique effects. After voting, players will begin with a random 1-cost champion and no items. In return, the selected areas will provide players with extra stats or special effects.

Therefore, players need to read the effects of the areas carefully and vote for the one that best fits their strategic intentions. For example, if you want to play team compositions based on major race-system thresholds, the area related to Bandle City is the most suitable choice. This is because this area can provide a Golden Spatula or create a slot in the waiting area and apply the race-system threshold of the champion standing there to the team composition.
No More Hero Cores
In Season 8, Hero Cores acted like an “insurance” ticket and helped players acquire essential champions with significant power. Players only needed to activate the related race-system thresholds to obtain the corresponding Hero Core. However, this will no longer happen in Season 9 as Riot has removed this system.

Of course, some 2-cost champions like Sett, Warwick, Swain… are still very strong when they possess their own Tech Cores in Season 9. However, the number of such champions in Season 9 is very limited and players will almost no longer have the “insurance” provided by Hero Cores.
Conclusion
With these significant changes, players will need some time to adapt to the upcoming Season 9. Hopefully, the above insights will help shorten this process and enable gamers to quickly find the most effective way to climb ranks in the new season.