Team Liquid was placed in the same group as Team MAD (Taiwan runner-up), and all Taiwan teams besides Flash Wolves are weak. Team Liquid may not be able to overcome KT Rolster, but they can easily get 2nd place in this group
100 Thieves was placed against Fnatic (the weakest seed 1) and Invictus Gaming (chokers), I dare to say they have a fair chance to advance in 1st place in a group like that.
If both happens, be sure the quarters will be Team Liquid vs 100 Thieves
Cloud9 has to go through play-ins, against Kabum (Brazil, used to be decent for wildcard standards, now a piece of garbage) and Detonation (Japan, no comments). I would not say it's the weakest group, but it's an very easy 1st place, and they'll destroy whatever comes in 2nd place from other groups, the only threat being the Turkish team, Supermassive.
After this, Cloud9 will probably get placed in group 1, against Flash Wolves, Afreeca Freecs and Phong Vu Buffalo. I wouldn't risk to say they're okay. Afreeca is definitely the strongest team. FW and PVB are trouble as well.
This is the year, NA is going to semis. Cap this.