The League of Legends Circuit Oceania (LCO) was the top-level of professional League of Legends competition in Oceania, founded in 2021 and hosted by ESL Australia and Guinevere Capital. The LCO replaced the Oceanic Pro League (OPL), hosted by Riot Games Oceania from 2015 to 2020. The annual season consisted of two splits, each of which conclude in a double-elimination tournament between the top five teams.
Before 2023, the winner of split 1 qualified for the Mid-Season Invitational (MSI), while the winner of split 2 qualified for the League of Legends World Championship. However, in 2023 and 2024, the top two teams from each LCO split were seeded into the Pacific Championship Series (PCS) playoffs and competed with other PCS (and later LJL) teams for a chance to represent the larger region at international events. LCO teams no longer qualified directly to MSI and Worlds.
On 20 September 2024, the LCO officially folded, with Riot Games exploring "new solutions" to replace it. It is currently unknown what league will replace the LCO for teams in Oceania and what role it will play in promoting teams to the new Asia-Pacific tier 1 league, the League of Legends Championship Pacific (LCP).