Instead of Nerfing Items, limit the Stacking of a single item per champion.
So no 3 Lockets on single Champion So no Double or Triple of an Item on a Single Champion
This will make players in TFT be Creative with Item combos vs Stacking 1 item 3 times to win the game or place Top 4.
I believe this is Best Solution, without nerfing items or Classes and its will promote Creativity in the Game.
[poppy-wink] 
Just remove items entirely. Its chess
If you really want to get rid of stacking have the second and third item lose effectiveness by some percentage. Just saying. I really don't care.
This is a dumb idea because sometimes players want to stack items for the raw stats. Just because two warmogs don't stack with their passives doesn't mean it is completely useless. Sometimes you can only fit 2 more slots for items and having 2 warmogs will give you just the right amount of health to reach warmog's heart without ruining your other 4 items. Sometimes, you need 2 lockets not because you are bad and don't know that locket actives don't stack, but because the stats on locket are just too good. For only taking 1 item slot, you can gain 60 magic resist and 30 armor. Do you know how ridiculous that is? With 2 lockets, you can get 60 armor and 120 magic resist for very cheap and is good in situations where the enemy has 3 or 4 champs who mainly deal magic damage and 1 or 2 who are ad/fighter. Another great example is how at a higher level, stacking doran items early is very strong and a lot of low skill players think players who do this are noobs, but it's a very low cost but quick power spike. Not being able to stack items is a terrible idea imo. It's already bad enough that we can't stack tear items. I get that a lot of salty people buy tears at end of game, but on some champs, two tear items was actually really strong. Ezreal was 1 champ who could benefit from this as his kit scales with both ad and ap so having both muramana and seraph's mana along with the ap and ad was not the worse things you could do.
Wait a minute, you are talking about tft holy shit i wasted my time typing that. But I'll just leave it there anyway lol
