Defeating Vanguard in the Tutorial level

[GhostBabel23]

While I do not recommend trying this with heavier characters, you could potential do this with anyone. Since Vanguard is designed to kill you in one blow, remove all your armor for additional speed. You also might as well remove that shield of yours too. If you're a magic user (Magician or Royalty), put your Catalyst in your shield holding hand so you can use the magic on the fly when the boss is turned around. Now the trick is to dodge roll behind him, or at least always to the left, whenever he swings. If done right he will never hit you. Wail away on him with your sword and avoid his butt bomb attack (he floats up in the air some, funny, but deadly at this stage in the game). Victory will reward you with his Demon's soul (which you can use to make an axe or absorb for points, which I recommend absorbing since he will appear again in level 4-1 and give you the soul again) as well as a journey to another realm. There you will find several more souls to be had. Just be careful not to use them until after you beat Phalanx in world 1-1 just in case you loose them.

[GameMaster]

It was done before. Once you beat his ass, you get summond to another world with the Fake Boss (Forgot name). In some point the boss 1HKO you, and you'll end up where you would turn if you haven't killed Vanguard.
Theres a video on YouTube.

[GhostBabel23]

Well of course it's been done before, you know the first sap who bough this game tried and on a first playthrough, especially unexpected, it's not easy. Obviously after you get used to the game Vanguard is the easiest boss in the game.

Also, it's not a fake boss, it's the Dragon God. The location you're in though is different then before so you would die with or without the cutscene killing you off.

[GameMaster]

Well of course it's been done before, you know the first sap who bough this game tried and on a first playthrough, especially unexpected, it's not easy. Obviously after you get used to the game Vanguard is the easiest boss in the game.

Also, it's not a fake boss, it's the Dragon God. The location you're in though is different then before so you would die with or without the cutscene killing you off.

Right! It's the Dragon God, I just watched the video ;)
I'd expect to get something better than just getting killed by a boss I'm gonna kill later, after wasting so much time killing that dumb Vanguard...