The Yoga Inferno is one of Dhalsim's Super Combos, introduced in the Street Fighter Alpha series. It returned in the Street Fighter IV series.
The move most recently appeared as his Super Art in Street Fighter X Tekken, where the move has an anti-air version called the Yoga Volcano.
Input
Street Fighter Alpha & Street Fighter IV series
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Marvel vs. Capcom series
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Street Fighter X Tekken
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Description
Dhalsim breathes out a large Yoga Flame which burns the opponent. He will breathe the flame in a flamethrower-like style and angle it up and down.
Street Fighter Alpha series
The move is executed by performing two quarter-circle forward motions and pressing punch. How long the flame lasts depends on the level of the Super Combo; the lowest level lasts a few seconds and does 3 maximum hits, Level 2 lasts a couple of seconds and does 7-8 hits, and Level 3 lasts quite a few seconds and does a total of 13 hits.
Marvel vs. Capcom series
Same as the Alpha series, but now done by performing a quarter-circle forward motion and pressing two punch buttons. It has almost the same properties as the one from the Alpha series, albeit the flames now last longer and spray wider.
Street Fighter IV series
The input remains, but the move itself is changed slightly; Dhalsim no longer breathes the flame in multiple directions, and keeps it straight ahead.
Street Fighter X Tekken
The move is executed by performing a quarter-circle motion and pressing all three punch buttons (or kick buttons for the Yoga Volcano). The addition of the Yoga Volcano gives Dhalsim another option to use against airborne opponents.
Tactics
It is very easy for a foe to be trapped in the flames and receive many hits; however, if blocked, it does very minimum block-stun, and will leave him wide open for a Alpha Counter, among other moves.
In Street Fighter IV, Dhalsim can combine Yoga Inferno with his Yoga Catastrophe and Yoga Teleport, since Yoga Catastrophe is slow enough for the player to perform this.