In the BRB, under the rule «what's in a name» p.501 section magic items, it is stated that magic weapons in that section can be any weapon type. Does this rule apply to any magic weapon (ie the ones in the lizardmen army book)? I'm particulary thinking of ScarVet+great weapon with «piranha blade»... 4 atk, str 7, armor piercing that does D3 wounds! Thanks!
A great weapon is a mundane weapon choice. If you also take a magical weapon it replaces the mundane weapon, so the scar-vet would use the piranha blade INSTEAD of the great weapon. It doesn't combine stats. Nice try though
The "What's in a Name" rule refers to the look of the weapon. Sadly, you can't combine the traits of magical weapons with the traits of mundane weapons. But, you can model your scar-vet with a great weapon and then in a game say "that great weapon? Actually a piranha blade today" and the rules back you up.
As a side note, anything that is a particular type of magical weapon will state it in the description. E.g. in the Wood Elf book there are several magical spears and bows and those are listed as such. ~gwh