Spring Fist was a Super Smash Bros. for Wii U doubles-only tournament hosted by Nintendo in Tokyo, Japan that took place on March 17th, 2018. The tournament occurred alongside ARMS and Pokkén Tournament DX tournaments. The event was first announced on Nintendo of Japan's website on February 23rd, 2018. It was notably sponsored by Twitch Prime. The tournament was streamed by SHI_Gaming.
The tournament had rules very similar to Tantalus' Recommended Ruleset, with a notable difference being that it was single-elimination. Registration was available for all three titles via Amazon Japan for ￥1.
Super Smash Bros. for Wii U doubles