I would estimate this mistake -- which most casual players would have avoided -- might have cost him, perhaps, 15 to 20 seconds in lost time.
So, at 0:00:08, Samura says: "Let's reset."
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The object of a 100% completion of Mario Sunshine is quite simple, actually.
You must collect 120 Shine Sprites and 240 Blue Coins. The Sprites (twinkling, rotating 8-pointed yellow stars with smiley faces) are earned after completing an "episode" of a "level" of the Mario world; in addition, sprinkled throughout the game are various Sprites that can only be won by some clever gameplay, often using newly acquired devices which augment the power of Mario's water-weapon.
My daughters and I played this game for years and years -- and at least one of my daughters (although not myself!) completed the entire game. I can only estimate vaguely -- but I suspect that they probably played for at least 100 hours -- perhaps more -- to accomplish this task.
In this video, Samura completes 100% of the game in 3 hours and 43 minutes, 15 seconds. All 120 Sprites. All 240 Blue Coins.
~ ~ ~
Understanding the SpeedRunsLive box on the left is quite simple: The name of the "level/episode" / the number of Blue Coins collected (in parentheses) / and the cumulative time. When an episode is completed, the cumulative time turns into a + or - figure, indicating the split between this run and the previous world record (held by Samura -- 3:48:00).
The actual gameplay for this run begins at 0:07:05. Mario's very first belly-slide (the quickest method for moving him straight ahead) results in a crash (see the stars?).
"Horrible," Samura exclaims. Nevertheless, he dispatches the first Petey Piranha boss quite quickly.
The next task is to chase down "Shadow Mario" and spray him until he "dies." Samura quickly picks up a Blue Coin before racing back to the big "M" where he will enter the next level. He cannot enter until Shadow Mario (resurrected) races back and paints that big "M" and he has to wait two or three seconds for Shadow Mario to finally show up!
"Hey!" Samura seems surprised that he had to wait those few precious seconds before jumping in. The clock reads 8:56 as he begins the final section of the episode; the previous record is 9:47:10; can he complete it in 51 seconds?
Once again, Samura fails to execute a clean belly-slide right out of the gate. I believe he curses in Finnish! But the rest of the run is note-perfect, as far as I can tell.
The split is in red -- 6:03. He must make up that time quickly if he wants to set a new record.