V-System
V-Reversal
A lengthy teleport, good for getting out of pressure.
V-Skill 1
Nash's VS1 lets him absorb one hit fireballs. Upon adsorbing, he gains a bit of V-Meter. It has a small hitbox and a target combo associated with it, giving it some niche usage outside of that, but it isn't very useful in those departments due to it's small hitbox and low damage.
V-Skill 2
Nash's VS2 is a buff V-Skill, where he takes a step back and poses, powering up his next Sonic Scythe. This alters the frame data on each version greatly, making the light version +2 on block, and allowing the heavy version to be juggled out of. This makes random Scythe pokes and cancels much more dangerous for the opponent and safer for Nash. You should be using this VS in any matchup where the opponent doesn't have a fireball.
V-Trigger 1
Nash's VT1 is Sonic Move. It's 2 bars, and causes Nash to teleport. He can teleport directly behind the opponent by just pressing HP+HK, or he can teleport above them with 2HP+HK. This is a great surprise VT that lets him get out of fireball pressure, punishing his opponent with essentially a full jump in combo. He can use it in combos, too, and unlike every other VT activation in the game, Nash's VT1 only scales 10% as opposed to 20%.
V-Trigger 2
Nash's VT2 is Stealth Dash. It's 3 bars, and gives Nash access to a few new special moves, one of which you do on activation. By pressing HP+HK again, Nash will dash forward. During this dash, you can press back to come to a stop, you can press kick for a somersaulting rising kick, or punch for a jumping overhead strike. You can juggle out of both the kick and the punch followups. There's a lot of creative set play with this VT, allowing for strong resets, side switches, and mixups. Although, VT1 is still generally preferred due to more leeway to V-Reversal and ease of use.