been trying to play zed recently and I'm having a huge problem with the mid/late game. When the enemy is grouped my only option is to pick the adc, mid, jungler, or support... but they're so tightly compacted (and are champs with such great synergy) that it seems like I can't really do anything but attempt to engage just to die. Any tips on being effective late as zed?
One thing I learned is to not get so kill hungry, but look for objectives sometimes its better to do that. When it actually comes down to team fights, you gotta know your champion inside and out to make the enemy adc run for their life. If you delay because you're too busy figuring out what to press, thats an issue itself.
hes not super useful lategame when enemies are packed together. thats just the definition of an assassin. zed has really good single target dmg but the tradeoff is that he has very weak aoe.
if you want aoe dmg in compact areas then i recommend picking up 
or basically any mage
you wanna fight them from afar with a W+E+double Q combo then following up with an R+auto+E to finish them off, with the extra R to disengage
if you have 
+ one of the 
items then you should be able to kill any tank with a full combo
