The ARMS North American Online Open was an official online ARMS tournament held on April 4th, 2020 by Nintendo of America. The event was first revealed on March 23rd, 2020 along with the announcement that each member of Top 8 would be granted 2500 My Nintendo Gold Points (equivalent to $25 USD). While it was never officially confirmed, the tournament was likely held to tie-in with the announcement that an ARMS Character would be coming to Super Smash Bros. Ultimate in June along with ARMS being free to play for 10 days via Nintendo Switch Online. The bracket was organized by a team of Battlefy staff alongside the help of Era. The tournament is currently the largest ARMS event of all time surpassing the 2nd largest, EVO Japan 2018's 318 entrants by more than 500 players. The tournament was won by AstroNinja0 with GoreMagala coming in 2nd and JMCANADA coming in 3rd.
While no official Nintendo steam existed for the event, a group of streamers were allowed to stream portions of the event including Top 8 and Grand Finals. This team was dubbed the United Streams of ARMerica and featured Casual ARMS, SAVE_ARMS, Mileve, Defur, and Tamashii Kanjou.
