Sonic Boom
Horizontal charge
Back (or Back + Down)
Forward
The horizontal charge on Hit Box is intuitive. Simply let go of your charging direction and then input your final direction and attack at the same time.
Flash Kick
Vertical charge
Left Hand: Hold Down (or Back + Down)
Right Hand: Tap Up + Attack
With the vertical charge motion, you can continue to hold Down (or Back + Down) while you press Up - this is due to the Absolute Up priority mentioned above.
In addition, you can use your right hand to press the Up and Attack buttons at the same time.
This is one of the most precise and strongest techniques in the game on Hit Box.
- - - - -
If you have any questions about Street Fighter on Hit Box, please join our community on Discord and visit the #2d-traditionals channel. In addition, be sure to explore the "Hit Box" and "SFV" tags at the bottom of the post and vist our SF Index for more How-To content.