ITT: we remember the good, the bad andugly. Mostly ugly. MOST CANCEROUS OFF BUILDS TO LANE AGAINST
I'll go with the top three I remember off the ol' dome. In no particular order:
AP Tryndamere, season 3.
This shit was beyond aids. No CD on ultimate, out healed any harass you threw at him, styled on you with that stupid spin and worst off, did mostly physical damage until getting lich bane. Then he just chunked you with lich bane procs and cries during CDs. Dude literally was the most cancerous split pusher ever.
Solo lane Soraka, seasons 2, 3 and 4.
There's nothing good you can say here. She spammed old starcall and reduced your MR to 0 if you tried to fight her, resulting in her shitting on you with minimal effort. You couldn't kill her through her heals either. Your choice was cheese her early, hope you get help or enjoy losing lane just because she existed. And if that wasn't bad enough, you got to watch her heal allies while giving them 200 bonus armor during heals lol.
AD Nidalee, seasons 2, 3, 4.
In theory, you can still do AD Nid but because it requires landing spears now, you can't waste people's time by split pushing and pouncing all over the map, rinse and repeat. And getting poked down was bad enough, not to mention she had heals, was reasonably durable and still had that retarded execute on cougar form Q. People bitch about Jayce now but Jayce doesn't have shit on old AD Nid.
Not quite on the list but most miserable experience with off build within the last season (from beginning of season 6 to now):
Bruiser Yasuo
Yasuo is a pain to play against but when he builds full damage, he is prone to burst or just raw sustained damage from certain fighters (Jax Irelia etc). But bruiser Yasuo? Absolute AIDS. For starters, it took the skill of actually playing him properly out of the equation. Who cares if you suck with him, just abuse Trinity procs + fervor + mallet and be unkillable while doing unreasonable amounts of damage. Still not as bad as the three above but my god, fuck that.