Build working in Update 19.5 PC (23/12/2016)
Build working in Update 184.108.40.206 (13/01/2017)
Ember is mostly known for her WoF, which is annoying and not end-game viable.
I started looking for a way to make her not only good against high-level enemies but, most importantly, fun to play.
The setup is similar to others that might have been suggested by others already, but the performance is on a whole other level thanks to the particular combination of equipment and abilities I focused on.
The build revolves and is made viable by a melee weapon which has been buffed in a previous update, so let's start from there.
After the buff and the new nightmare mods, they can reach 100% status with just 2 dual elementals + drifting contact.
Base damage is only heat. Therefore, it can be modded for Corrosive + Heat or Viral + Heat. Since the weapon deals no IPS and status chance is 100%, you will always proc one of the 2 elements. This means that you can stip armor very quickly or halve the health of the enemies and deal Heat damage over time.
Heat damage usually performs badly at high level. However, in this case it is actually very good thanks to Ember's second ability.
The build is the following: https://goo.gl/Ek95wQ (the last slot is for drifting contact)
NB: I modified the build. See at the bottom for comparison.
The frame build is focused on power strength. Her 2 gives a HUGE boost to heat damage. Perfect for a weapon like the twin basolk. Unfortunately, heat procs do not stack like slash/toxin, only refreshing the duration of the proc, but at least you can stunlock enemies.
I use Growing Power as aura because of the 100% status chance and the corrosive damage on the melee. It is one of the few cases where I do not find CP necessary.
1 FORMA, 1- or 1v https://goo.gl/1fgO9S
I used them both and they're both extremely good.
Of course, if you're willing to go a few steps further, you could add an exilus adapter and two more forma to fit in Power Drift. You could also replace Intensify with Blind Rage (whatever rank), but I personally do not find it necessary and I like the positive power efficiency. I would recommend Blind Rage only if you have an Arcane Energise equipped or a Trinity in the squad. You could also max Transient Fortitude; I'm too lazy to add more Forma.
If you choose to change the aura polarity, add one forma. I do not find it necessary; if you really want to, change it to a - and use CP or ES.
Moreover, for teamplay I suggest one of the strenght mods for any of Ember's augments, depending on what most suits your playstyle: Fireball Frenzy to allow your teammates to exploit your 2nd ability's debuff; Firequake for extra CC when needed, especially when reviving teammates; Firefright for the same reason, but I personally do not like this one too much.
Naramon is needed to stay alive and increase your crit chance.
No arcane is needed. If you use one, it's entirely up to you and will only make the build more powerful.
If I had to suggest one, it would be Arcane Energize to help with energy regen. It would also allow you to sacrifice some efficiency for even higher power strenght.
Bring any Primary and Secondary you want. I'd recommend one that allows you to restore health, since Life Strike does not fit in the melee build. Therefore, the choice is narrowed down to syndicate weapons or Furis+Augment.
Obviously, mod them for fire to take advantage of the damage boost.
Bring any companion you want. I'd recommend a Kavat. In alternative, I'd use (Prisma) Shade or Djinn.
How to use.
Activate Naramon as soon as it's available.
Always start any encounter with a slash attack, since you will have guaranteed crit and go invisible.
Use her 2 in a group of enemies and start slicing them. I wish there was an augment to spread it like banshee's sonar. Anyway, the 100% status chance will strip the armor extremely fast or halve the health, while the huge debuff to enemies will increase your damage and the heat damage will stun them.
Moreover, you will soon start to crit on normal attack and redcrit on slide attacks. This means that you will almost always inflict critical statuses or redcrit statuses.
Importantly, pick up energy orbs, you need them both for energy regeneration and for increased power strength.
I've always disliked Ember since she performs bad at high level and all Ember users do is activate 4. With this setup, I solved both problems.
She performs well at high level. I managed to be able to deal against level 200 enemies solo, and I could have gone on more.
Most importantly, playing her this way is actually FUN. I don't consider pressing 4 and standing still in a corner as playing, and certainly not as fun.
I modified the Twin Basolk build. https://goo.gl/kLdtdj
Essentially, I swapped Primed Reach for Molten Impact. While the extra range gives you a higher QoL, the extra damage is substantial. An alternative would be to use Fever Strike to skewer the status chance in favour of corrosive proc. I do not deem it necessary, given the 100% status chance. Moreover, the benefit of using Accelerant would diminish.
I did some number crunching to compare the two builds, for those who are interested.
Damage is for each combo multiplier and considering ONLY SLIDE ATTACKS. It is a Blood Rush + Maiming Strike build after att. Of course, normal attacks, leap attacks, wall attacks etc have different damage values.
"Base" damage refers to the ensured damage given the current crit level, "Crit" damage refers to the possible damage given the crit chance at the current crit level. At just 1.5x, you will always red crit and the multiplier will scale accoding to the current crit level.
For the nerds, damage multipliers are reported in the following tables.
Table 2 considers only Crit Multipliers. As you can see, Naramon's Deadly Intent does not affect The critical chance up to 3x Combo. After that, it might help you scale quicker to the next critical multiplier, but I have not tested it. Probably not though, since the Twin Basolk's base crit chance is 5%, and with a maxed Deadly Intent it becomes 6.5%. Therefore, you could consider to disable it, in order to activate Naramon's invisibility earlier.
As I said, that's just considering Crit Multipliers. However, we have to factor in also the Combo multiplier boost to damage. Therefore, the real multipliers from the base damage in each build are:
MOREOVER! Those multipliers are for Normal Slide Attacks. However, we still have to factor in Accelerant's buff to Fire Damage! Depending on which Ember Build and which Twin Basolk Build you choose, the extra damage multiplier is:
Mind that the multipliers of Table 4 are MULTIPLICATIVE with the ones in Table 3. I leave the calculations to you.
Long story short: regardless of which builds you choose, you can see how the Ember + Twin Basolk combo is devastating :)