Fifteen Mercer Island lacrosse alumni joined forces in Vail, Colorado over the Fourth of July weekend to participate in the Vail Lacrosse Tournament as members of Team TW-21. The Vail tournament is widely regarded as the most prestigious annual club lacrosse tournament in the world. Most teams in the tournament are composed of alumni from NCAA Division I-III programs and team TW-21 was the only team in the field of 18 that was composed primarily of alumni from a single high school.

TW-21 began the tournament with two close losses but closed the tournament with two straight wins. The first was a 16-14 loss to an alumni group from Rochester Institute of Technology and the second was a 15-14 double-overtime loss in rainy and muddy conditions. As TW-21 adjusted to the altitude and unique rules (which included a 2-point arc and 30 second shot-clock), their play improved. Team TW-21 finished the tournament with a 14-6 win over a NCAA Division III team and a redemption 15-13 victory over the same RIT alumni team they faced in the opening round. The team played well, finishing with a 2-2 record.

Team TW-21 plays to honor Tim Wettack, a 2007 Mercer Island Lacrosse captain and All-State defenseman, who played as #21 during his time at Mercer Island. Mercer Island alumni spanning the graduating classes of 2007-2013 participated in the tournament.