History of Chasing Flame

Chasing Flame is a triumph for Warlocks: as a Dawnblade, get kills with Firebolt Grenades.

How to complete

1. Equip the Dawnblade subclass on a Warlock.
2. Equip the Firebolt Grenade (Solar grenade that fires bolts of damaging Solar Light at nearby targets and scorches them). Per Destinypedia, the Touch of Flame aspect raises its target search radius and maximum target count, which helps rack up kills.
3. Farm groups of weak enemies in Lost Sectors or patrols, throwing grenades into crowds.

Unconfirmed

A search snippet suggested the target is 200 kills, but I could not open a page confirming that, so check your in-game triumph. The seal or reward is not confirmed.