This is what the effects say.
Burning.
Dash leaves a trail that deals 5 per second.
Steal gives you that hp to your max hp.
Burst requires 7 kills from steal.
Crescendo. Forged with fiery flames and a demon's eye, the Crescendo ascends from its ancient sleep with a thundering tone. Normal: 15.
Dash: 37.5.
Steal: 35% current hp.
Burst: 115.5. Burning.
Dash leaves a trail that deals 5 per second.
Steal gives you that hp to your max hp.
Burst requires 7 kills from steal. 43,400.