Looks pretty good, though the wad does need INFO and CREDITS.
Also I think MaxAmount 1 is a little restrictive. Default max amount
would be better, I think.
Interesting note about the Shadow power: Two can be used at once to make a person fully invisible. Not sure if this has any effect on monsters (outside of Strife perhaps), but it would be neat if you made the main artifact a CustomInventory instead, and had it give PowerShadow twice. (Or at least use PowerInvisibility, and give it a high Powerup.Strength, like 90, to make the user nearly inviible.) This would better set it apart from other invisibility powerups.
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