The Long Sword has a motion value of 200 on backstab, 250 on riposte, and 60+225 on Hornet Ring riposte.
All weapons have motion values assigned to each attack, which are modifiers to AR that are associated with the attack being used.
A neutral one-handed tap R2 will combo with the follow-up R2.
It can be a good idea to hold the R2 for a moment to get past delayed rolls and parries.
While it doesn't true combo, the delay of the R2 lines up with the duration of a medium roll, letting the attack connect outside of the opponent's i-frames.
Being a standard straight sword, an effective combo for PvP is R1+R1+R2.
While in stance, use normal attack to break a foe's guard from below, and strong attack to slash upwards with a forward lunge. Inflicts reliable standard damage, as well as high thrust damage. A balanced, widely-used standard straight sword.