Here is the full list of all 15 Lethal League Blaze achievements.
Play 500 matches
Play 1000 matches
Beat the arcade mode with every character
Beat the story mode
Get a checkmark on every event in the story mode
Hit the ball back and forth in Lethal Volley for 16 times
Hit a goal in Strikers with a ball of at least 250 speed
Reach a ball speed of one million
Beat the arcade mode without using any continues
Beat the arcade mode
Bunt the ball at 1000 speed or above
Hit three players in a row
Play 100 matches
Rally the ball back and forth for at least ten times
Reach a ball speed of one thousand