German technique for fighting foes in armor. (You can also strike with the pommel that way.)
A longsword is a pretty versatile (beyond the D&D sense) and fun weapon. Generally, if you're fighting someone in plate, you can hack at them with your blade all day without doing much to them. So you either go half-sword (one hand on the hilt, one on the blade) and use your sword like a spear/staff/wrestling implement to either jab the point into a weak point in the armor, clobber them in the head with the pommel/crossguard and/or haul them to the ground and then stab them or you flip your sword over and use it like a war hammer.
