@Nen
There's a shortcut to get to Adjudicator location from near the start of the level, but it requires carefull rolling. So make sure you aren't burdened before attempting it. You don't have to sprint at the wall, and some have done it from a standing start at the right place.
When you enter 4-1, and you encounter the two archers shooting from above the first fog door, there's a tower to the right that you can access by climbing the stairs in the left tower and going across the rampart where the two archers are.
Remember, at the bottom of the right tower is where you pick up the copper key to free Blige, and there is a trap down there if you fall down. As you walk onto the top of this right tower from the walkway, you can go left around and down the stairs, or if you look right towards the far corner you will notice a part of the wall that is crumbled and is missing some blocks.
From the top of the tower, if you run and then roll toward the broken part, you will land on top of the tower wall instead of falling onto the stairs. Sometimes you will see a message on the ground like "Run Here" , and sometimes people leave a message on the top of the wall where you should aim to land.
Once you're there, look down and see where the wall below separates the starting area on the right (where you picked up the Talisman of God under the tree), and you can fall down to your left (down to where the HP regeneration ring is). This left path will take you right next to the area with the last staircase down to the Adjudicator (and it's a great way to rush the crystal gecko on the ledge).
This is from the Demon's Souls wikia, i've tried it myself, but only got it right one time out of 4 :P So in reality, there's a shortcut to Adjudicator, but it's really hard to get find it properly.
You don't have to fight the Vanguard, but you'll need his soul in order to make the Dozer Axe.
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