No video footage survived of the Slamfest '99 Super Smash Bros

The year was 1999 and recording was by no means as simplified and widespread as it is today, but Nintendo's Super Smash Bros. 64 promotional event in Las Vegas was indeed recorded, in fact, it was actually broadcasted live

Lost Media – Page 2 – The Maurice Bear Times

Slamfest '99 aka Super Smash Bros. LIVE (lost livestream of promotional event for Nintendo 64 crossover fighting game; 1999) - The Lost Media Wiki

Super Smash Bros., Smashpedia

Super Smash Bros. - Super Mario Wiki, the Mario encyclopedia

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Lost Smash Bros. Slamfest '99 Photos Put Pikachu, Mario, and Yoshi in a Real-Life Ring - IGN

No video footage survived of the Slamfest '99 Super Smash Bros. wrestling event, but these photos just surfaced

New Photos from the Lost Super Smash Bros. Slamfest '99 Event Have Emerged : r/nonmurdermysteries

The Lost Nintendo Event that Might Be Gone Forever - SLAMFEST '99 (Update #2)

New Photos from the Lost Super Smash Bros. Slamfest '99 Event Have Emerged : r/nonmurdermysteries

Smash Bros. news, videos, tournament results, streams and more

New Photos from the Lost Super Smash Bros. Slamfest '99 Event Have Emerged : r/nonmurdermysteries

Smash Bros. news, videos, tournament results, streams and more

New photos from the lost Super Smash Bros. Slamfest '99 event have been uncovered! : r/retrogaming