I think Riot had own format for Master Reykjavík. This is just my suggestion to a Master competition with 12 teams in 15 days (April 10-24).
3 stages: Play-in group, Main group, Knockout
Seeds are based on last Champions' result: EU>LATAM>SEA (now APAC)>NA>KR>BR>JP
Play-in seed
- pool 1: KR#1- EU#3 - APAC#2 - EU#2
- pool 2: BR#1 - BR/LATAM#2 - JP#1 - NA#2
Main seed - EU#1 - APAC#1 - LATAM#1 - NA#1
Play-in group stage (10 matches in 5 days)
- 8 teams are drawn in 2 groups
- Double elimination, all matches are Bo3 (5 matches each group)
- Two teams each group qualify for Main group
Break in 1 day
Main group stage (10 matches in 5 days)
- 8 teams are drawn in 2 group
- Double elimination, all matches are Bo3 (5 matches each group)
- Two teams each group qualify for Knock out
Break in 1 day
Knockout stage (3 matches in 3 days)
- 4 teams
- 1st place plays against 2nd place from other group in semifinals
- Single elimination, all matches are Bo5
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