Vision (ビジョン, Vision) is Shulk's down special move. It is a counterattack that is notable for having one of the longest counter windows in the game, along with being the only one to have two different counterattacks depending on directional inputs.
Types of Attacks
The move involves Shulk getting into a countering stance, then retaliating with a slash from the Monado if he is hit. Shulk says "A Vision...!" ("ビジョン!", Vision!) or "I see it..." ("見える...") while retaliating, and a translucent blue background appears during the counterattack (which is the backdrop used for Visions in Xenoblade Chronicles).
If no directional keys are held down, Shulk performs a large, slow forward-sliding upwards slash, capable of hitting opponents a distance away from him; this has one of the longest horizontal reaches of any counterattack, along with Double Team, Substitute and Toad. If forward is held during the counterpose (only while Shulk is grounded), he will instead perform a dashing slice through the opponent. This variant is much faster, sends opponents behind him, and has higher knockback growth (84 → 94), but has the tendency to miss more often due to the attack's speed and Shulk's forward momentum.
The regular counterattack deals a minimum of 7%/10% (beam/blade), and otherwise deals x1.3 the damage of the move that it countered. The forward counterattack has the same multiplier, but with a minimum of 10%/13% (beam/blade) instead. This counter will one-hit KO when countering a hitbox that deals at least 35% damage, and is one of the strongest counterattacks in terms of knockback, along with Ike/Roy's Counters and Corrin's Counter Surge.
During the counterattack, Shulk gains intangibility right until he performs the slash. In addition, activating the counterattack slows the victim down for a brief moment (similar to a short-lasting Timer), and the slashes themselves are unblockable. However, opponents can sidestep or roll if a low-cooldown move triggered Vision, while projectiles and thrown items do not slow the victim down. Additionally, it is inadvisable to use the move offstage, due to the counterattack's slow startup and the fact that Shulk continues falling through the move.
Compared to other counterattacks in Smash 4, Vision begins countering on frame 7 (which is faster than most) and is tied for the longest counter window in the game when fresh (35 frames, the same length as Double Team). This makes it capable of countering attacks even when the readying animation seems to be complete, making the counter extremely effective when used unexpectedly, especially when considering its other strengths.
Vision's weaknesses include being one of the two counterattacks with a sourspot in Smash 4 (along with Palutena's Counter) due to the Monado's blade and beam hitboxes. Additionally, the counterattacking window becomes shorter (decreasing by 11, 8, 5, 4, then 2 frames) every time it is used in succession (regardless if the counterattack is triggered), eventually reducing Vision's counter window to a mere 5 frames if it is spammed, which does not happen to any other counter (Witch Time's effect when successful decreases, but the counter window itself remains the same). The window length is fully replenished when 15 seconds pass without using Vision, or once Shulk is KO'd and respawns.
Every Monado Art other than Jump has an effect on Vision's damage output, damage cap, and knockback. Speed and Shield will decrease damage (and knockback as a result), Buster will increase damage and decrease knockback, and Smash will decrease damage and increase knockback. These changes are significant enough that they affect Vision's knockback at 0%, such that Vision will take longer to OHKO while any of these Arts are active, to the point of requiring a move that causes Vision to deal the counterattack damage cap.
Special Move customization was added in Super Smash Bros. 4. These are the variations:
Visions play a key role in Xenoblade Chronicles; as the wielder of the Monado, Shulk occasionally foresees major events, usually those of a tragic nature. Once he learns how to handle these visions, he uses them as his guide, usually to prevent foreseen deaths. Visions also play two roles outside of cutscenes. One role is informing the player that a recently picked-up item is needed for an upcoming quest. When that happens, that item is marked, to alert the player to keep the item for the quest. The other role appears in battle when an enemy's attack may inflict major damage or status to the victim, in order to alert the player to take measures in averting the vision (via preventing the enemy from using the attack, redirecting the attack away from the intended victim, or improving the victim's defenses to ensure that they could survive it). The two lines Shulk can say when Vision activates in SSB4 are direct quotes he uses when Visions activate during combat, although re-recorded.
Both versions of the counterattack have animations similar to two specific arts in Xenoblade Chronicles: the regular slash Shulk performs is reminiscent of Stream Edge, one of his physical Arts in which he takes a step back and takes a large horizontal swing forward, capable of hitting multiple enemies with its range, while the faster-dashing slash resembles Dunban's ether art, Thunder, which forces daze on opponents who are behind him if he has an active aura. While either technique is ill-advised for situations in which a vision may appear, they could technically be used as a counterattack.