After a lot of unsuccessful research into the allegedly buggy "Immolate by Fire" achievement on Makeb, we finally figured out how to complete it.
First, this success requires us to kill 100 flaming makrins on Makeb. There are different types and sizes. It ranges from small and weak to large and elite. As a reminder, this is what a makrin looks like:
To complete this achievement, you will need to kill 100 of these cattle while they are under the effects of fire damage. For that all the classes will not be equal. It is not possible to do this with an Inquisitor or a Consular and for the classes where it is possible it will be necessary to use a certain combination of spells or to have a little luck.
To get started, head over to Makeb with a Mercenary and choose the discipline Innovative artillery. Don't forget to equip yourself with your fuel gas cylinder. Not having tested with a Specialist in pyrotechnics we cannot guarantee that it works but, the cylinder to be equipped being the same, there is a good chance that it is feasible. Likewise, if you come with a Commando or Vanguard this should work too but we cannot guarantee that. For the other classes some rumors circulate to say that the Marauder and the Sentinel could also be able to supplement it with one of their discipline but we were not able to find which one.
You will find makrins in areas of the frinn table or telemur table. Then you just have to kill them making sure that they are carrying the burn effect of your cylinder.
Also note that this counts on all makrins including the smaller ones. So you can kill the weaker ones with chain shots so that they have the burn buff when they die, and if they ever die on the first hit don't worry they will count too. Finally if you meet people in these areas know that success is also completed in a group.
And now, to your blasters!
