Mainly Poppy and Heimerdinger.
Most of the teams played the entirety of worlds woukd have been easily countered by a poppy support and/or a heimer botlane.
We only saw one game of Poppy support and she dominated the game. A couple other poppy games that kind of spiraled out of control, admittedly enough. We only saw one (maybe two) games of heimer.
I dont understand why teams didnt play them.
Tr4shB4NSYST3M5 votesThinking about it now, 
W would have gotten so much value vs literally all 3 FPX comps in the finals.
GeminiRune3 votes#EXACTLY
ChompyWulf2 votesIt might have helped, but I'm not so sure. Game 2 G2 clearly planned on doing Grag/Yas, so no way does Poppy come in. Game 1 G2 was quite competitive, and Kench offered some anti-dive defense. And at the end of the day, a huge problem for G2 wasn't just protecting their back line, they NEVER got into the FPX backline at all.
Poppy may have helped, but when GimGoon and LWX combined only had one death, there are other big problems that Poppy just doesn't solve.
Galiö2 votesCould have sent Yasuo mid or top and Gragas jungle. Had Poppy Support. Just example for Game 2.
GeminiRune2 votesI was talking about that with a few folks after the finals. Basically Poppy was the most talked about, especially in the amount of engage comps that conspired in several games. That and I know I'm a fan of competitive Poppy cause I really feel like the W buffs really upped her value
Galiö1 votesI've been talking about it since play ins. Like if you're against a naut, kaisa, lee sin, renekton you can easily play poppy into that lol
GeminiRune1 votesAll tournament yo. She was absolutely a viable pick. Put us in as strategic coaches or something
Full Brain2 votesYou have to be good at those characters which is why they didn't get played much. There was a lot of room for different compositions this year but most of these teams are basically comprised of young one tricks who can play like 2 other characters barely at an acceptable level for worlds. FPX targeted Jankos with this and used G2's reluctance to ban out Tian's picks because their character pools overlap to gain an advantage by just picking Tian's character early. FPX won every draft by focusing on jungle mid pressure spreading to the rest of the map. G2 lost every draft by trying to show off and look clever.