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CS88WGS 4 l
Attack bonus if proficient +3
Weapon die ([W]) 1d10
Type melee
Handedness two-handed
Proficiency category military
Weapon group
Weapon properties
Price 30 gp
Weight 8 lb.

A greatsword is a military two-handed melee weapon in the heavy blade weapon group.[PH:218]

Ardents, avengers, barbarians, battleminds, fighters, paladins, rangers, wardens, and warlords are proficient with all military melee weapons, including the greatsword. Assassins and swordmages are proficient with military heavy blades, including the greatsword.

Other classes do not have proficiency with the greatsword as a class trait, but any character can become proficient by taking a Weapon Proficiency feat.