Fredrinn gains 1 Combo Point that lasts 5s each time his skill hits a non-minion enemy, up to 4 Combo Points. His Ultimates cost different numbers of Combo Points.
Fredrinn stores 100% of the damage he receives as Crystal Energy, which decays after 5s at a rate of 10% Max HP per second.
Fredrinn can convert the stored Crystal Energy into HP by 20% of his damage dealt (10% for damage dealt to minions). Gaining a Combo Point resets the decaying timer.