Welcome to Set 4.5

When the first mid-set update, Galaxies 3.5 came out, it breathed new life into TFT, and made a good set and fun game even better than before.  Set 4.5 is not looking to continue that trend.

Festival of Beasts is Just a New Coat of Paint

Rather than really change up the formula, mid set updates are supposed to build upon what a set is doing well, while taking out or changing around the stuff that doesn't work.  Last mid-set we saw the removal of Kayle, which was a balancing nightmare, with only Vayne and Urgot as truly problematic additions.  Now we're looking at Aurelian Sol, Tryndamere, Olaf, Samira, Swain, the return of Kayle, and the bizarre buggy mess that is Sett. Ornn is also looking to have some problematic gameplay, but I think the jury is still out on if that's really the case.

 Problematic mechanics in TFT are pretty well defined:

•  AOE Spells that hit everything (Asol, Kayle, Samira)
  
• Reset Mechanics (Darius, Talon)
  
• Drain Tanking (Swain, Tryndamere, Olaf)
  
• Scales with game duration (Veigar stacks, Ornn artifacts) 
• 1 Hit/1 Spell kills (Lee Sin, Urgot) 
• Aggro Drop (Set 3.5 Vayne, Set 4 Shades)
• Perma Stuns (Set 1 Volibear, Set 2 Olaf)
  

While a lot of these mechanics can be fun to play with, or give an important strategic tool, too many of them at once destroy the fun of the game; watching your team fight as a team.  Set 4.5 didn't remove problematic champions, and added a huge assortment of them.  While I can't predict if this set will be fun (I'm happy to give it a few weeks), I can say for certain it's unbalanceable.