Who dies

[Thorn]

If me and my opponent are both at 1 life and I have a {Blood Artist} in play and he sacs a {Soulcage Feind} then what happens? who dies?

[Thorn]

even without the artist who dies?

[BlackJester]

Who's turn is it?

[Sagemaster]

even without the artist who dies?

Tis a draw

[Thorn]

Who's turn is it?

Does it matter?

[BlackJester]

Without the artist, you both die.  With the artist, APNAP order would mean the active player puts their triggers on the stack first, then non-active player's.

[Thorn]

So he dies?

[BlackJester]

Right.  And if it's your turn, you both die because the Fiend's ability will go on the stack last.