Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
Plans to break league into 4 regions and applying franchising business model was postponed until season 2019. Best-of-three format with dividing teams into two groups has been replaced by a Double Round Robin Format with "best of one" matches in a single group owing to EU LCS viewership falling.
Second-tier competition in Europe from season 2014 to 2017 was Challenger Series. In season 2018 it has been replaced by European Regional Leagues (ERLs). Promotion Tournament was cancelled, the European Cup provided in addition to ERLs.