Guessed by GoOnKid
"Iet, wiet, waai", was a phonetic sound with which we meant an easy combo for Siegfried. It's like saying "Hiss, whoosh, wham", or some other trio of 1960s Batman phrases. This even became synonymous with the character's name, like "Oh, you're playing with Iet, Wiet, Waai again". The combo is just spamming the vertical slash move. It's a classic noob tactic because with Siegfried's enormous sword, it means no one really can get close anymore and it's likely you'll win unless someone is good enough. This also worked with Nightmare, which is basically Evil Siegfried. Obviously, I played as Nightmare.
During the Dreamcast days, we had a couple of family friends, or rather, they were mostly co-workers of my parents, who came over from time to time to play some local multiplayer. These games included 'Virtua Tennis' (#43), 'South Park: Chef's Luv Shack' (yes), and this game here, 'SoulCalibur'. SoulCalibur was probably the most popular of these, because it was an amazing game. This game was so great, that the PlayStation 2 didn't seem like such a big deal and none of us got one. Really, no one.