Craft Construct requires CL 5 - is it useful at that level?

[Segev]

On mobile, but they seem to lack the haunting of harrowstone alternate price tag, aye.

Weird. Maybe it didn't survive the transition from the old host site.

As for waxwork hydras, I'd say heads can be severed, but can be reattached by holding them to the stump.

Decapitation shouldn't really kill them, tho, but being disarmed like that certainly helps.

Well, given that "hydra heads" definitely improves their melee attacks, the waxwork unquestionably retains it, so holding the head on the stump may be foolish; you want to just wait 1d4 rounds and grow a new pair of heads.

Decapitation kills neither constructs nor hydras, so yeah, cutting off the heads won't kill them.