Simulacrum

[TheGogmagog]

Okay, I'm creating several simulacrums of key bad guys for my Shackled City campaign, and I'm wondering what type of creature a simulacrum is. Is it still the same type as the creature it is created from or does it have the Construct type? The spell description doesn't say.

I believe it's a partially real illusion from the spell descriptor (shadow). Reference:Is Simulacrum subject to abuse? There is also this discussion, which goes on quite a while, but points out that Frostburn has an adventure with a simulacrum Old white dragon. It's still an old dragon, with half HD. I'm curious if it has spellcasting ability or type, I don't have frostburn though.
"Effect: One duplicate creature
Simulacrum creates an illusory duplicate of any creature. The duplicate creature is partially real and formed from ice or snow."

I'd also say that the CR is part of the creating caster, just like summoned or gated creatures. I would total the Exp expended though and add it to the caster's XP to determine his real CR. It would Probably only total to one level difference though, if that.