Guild Wars 2

I recall a cut scene promoting GW2 before it was released showing a ranger firing some arrows through a fire wall passing through igniting, hitting a mob and setting them on fire.
How is this achieved ingame ?

That was a combo. Notice how many moves are listed as either combo fields or combo finishers. Using a combo finisher in a combo field results in a bonus effect, in the case of firing arrows, projectile finishers, through a fire field the arrows then cause burning to their target.

Pretty much just shoot your arrows through any fire field created by another player. You can also create your own fire field with the utlity skill ‘flame trap’ but this is going to be a bit impractical to do solo just because of how traps work.

Pity, seems a bit like false advertising to me. Never seen it happen in game.
Combo finisher in a combo field ???

It happens in game all the time, mostly when there are 2+ players in close vicinity. You might also want to check the Wiki page on combos.

You can actually do this one yourself with a bit of weapon swapping. Equip a torch as an offhand, use bonfire, evade or run backwards, switch to a bow and fire arrows through it.

You can also check how many combos you’ve used to kill an enemy by going to the community page of the achivements tab in the hero panel. You’ve probably done a few during busy DEs and things without even realising.

If you hover over your skills you can see which ones can be used to create combos. In general anything which creates an area effect, like the ranger traps, is a combo field (the first part) and then all kinds of skills are combo finishers. For example all ranger bow skills (I think) are projectile finishers, which means if you fire them through a combo field you get a special effect when they hit.

SteveK.5827:

Pity, seems a bit like false advertising to me. Never seen it happen in game.
Combo finisher in a combo field ???

I know such a disgrace, you should write them a strongly worded letter to let them know how much this has inconvenienced you. Perhaps you could sue them on them on the grounds that you have not yet grasped the basics, thus it is false advertising to show you a move that you don’t know how to do.