First things first. Nastyblade is a highly skilled Reg/Sed from Gameranger. He has ~300 games here, but I'm sure whoever has seen him in action, remembers his unique playstyle. Since he's Czech-speaking, I don't think he can present his build himself, so I'll be his self-appointed promoter Anyway, I'll analyze his build and the rationale behind it, and provide a link to a replay of the match I've played against him today. I believe this match showcases his build/playstyle's strengths adequately.
1. Heal 1
2. HW 1
3. IG 1
5. IG 2 + HW 2
6. Heal 2
7. Heal 3
8. Counter Healing
9. IG 3
10. Pounce 1
11. Silence 1
12. Silence 2
13. Heal 4
14. Pounce 2
15. Life's Child
Start w/ Monks, TP
WR 3 - Plenor, Vlemish, Scalemail, health pot
WR 5 - Boots of Speed, health and mana pots
WR 7 - J-Treads, Boots of Speed -> Nimoth Chest
Priority on having high speed, mana and armor by sacrificing hp. Using pots, not sigils. No Pounce, no Silence until later mid game. Justification: you don't need a lot of hp when you are that fast; +50% temporary hp is laughable when you are that squishy; high armor is a necessity when destroying towers or ninjaing portals; you are extremely mobile and should stay out of trouble, and assist as needed by healing/removing debuffs.
This build is extremely efficient early to later mid game, when the team has a very good carry/DD (in the replay below, it's ppap's UB), and the team is constantly on the offensive. I've seen the very same build fall flat on its face if the game lasts too long or the team having MCP/speed Sed is forced to play it defensively. Low hp target = freebie kills. Late game chain-stunning is a doom of every speed build in existence. In other words, too risky and inconsistent, and I've seen it fail as often as it succeeds in higher-level matches. That said, Nastyblade surely is a unique Sed player and he pulls off his high-risk build admirably well.
I think it is an original build/playstyle by an underrated player that certainly deserves more attention than it gets.
The replay: http://www.gamereplays.org/demigod/replays.php?game=51&show=details&id=188405