What happens when I lay my second or even third {teferi's puzzle box}?
Each puzzle box would add it's ability to the stack and you would have to exchange your hand multiple times
Some crazy💩, that's what happens
Great when looking for {battle of wits}
Only if you can somehow cast the battle of whits at instant speed. Otherwise you get sad as you draw it and have to wave bye-bye to it on the next Teferi trigger on the stack.
{leyline of anticipation}
As stated above each box trigger will go on the stack and resolve seperately. I use {Strionic Resonator} to copy the trigger in my {Nekusar, the Mindrazer} EDH for extra damage on my opponents turn.
But it's so fun combined with {Underworld Dreams}
{Psychosis Crawler} is also nice.