Whats tiebreaker for groups?

seems like a lot of teams will be tied in record for the 4th spot out of groups, whats tiebreaker? Is it head to head result? Round differential?

Probably h2h, aka next week NRG vs Guard will likely determine 4th spot in playoffs in group A.

if 100t wins this tsm out
it will be between nrg and guard

H2H in two-way tie
Map Diff in anything else

If the tiebreaker is H2H why GHOST is first instead of XSET? I read about H2H being the tiebreaker in a 3 way tie, in normal conditions I think is map percentage, then round percentage, if im right, NRG wining against 100t, TSM is out cause 100t have at least 5 rounds and will lose tops 6 rounds, which is a better percentage than TSM can get