[1.3] CI crit firetrapper

I decided to scale fire trap on levels and critical chance (you can go fire / burning / spell damage + ignite chance, but there is plenty of guide about this already, look them up if you are interested). Our offense is based on generating power charge (using assassin's mark, or ice spear / pcoc in curse immune maps) to get enough %crit chance on fire trap (you can manage to get around 60% chance), and destroys packs ; we use elemental proliferation because it is OP and clears packs even if we don't get crits on fire trap/

For defense, we get a decent ES (7500+) for a staff build, but we can't leech because of the trap, so i decided to go regen (with zealot oath). It is pretty hard to get liferegen from the tree, so i use the blood dance to gain regen, generating frenzy charges with blood rage. You can get 3-5% life regen with that, which effectively is 250/450 ES regen/s. Also, you shouldn't be hit much anyway since all you do is run everywhere.

Example level 80 tree

My current tree @ 85


Explanation :

For this build to work, you need the +3 max power charge (duration for power charge is cool but not mandatory if you feel like you can play without), the high explosive notable near shadow start (because of 10% elemental resistance penetration), area of effect nodes (templar and witch), 300% crit chance (for spell), chaos inoculation, zealoth oath and at least 150% increased ES. If you have mana issues, you might need to grab sovereignty between templar & witch.
Once you have all of this, grab either %incr ES (nullification at shadow start), or more crit chance/multiplier (serpent stance / arcane potency notable between templar/witch, grab the last nodes near assassination/doom cast @shadow start), max mana / mana regen nodes if you have issues with mana.
For leveling, just do a regular life-based firetrapper, until ~80 (you need quite a lot of skill points for this build imo) where you can respec.

Bandits :

Normal : skill point
Cruel : skill point
Merciless : You can get either Kraityn's reward (+1 frenzy charge) or Alira's reward (+1 power charge). The frenzy charge is more defensive (it's 1% life regeneration), the power charge more offensive (it's 50% crit chance after all). Personally i took the frenzy charge but it's up to you.

The biggest problem with this build, if you take voidbringer (as you should, it's just too good), is the mana. Your firetrap will cost around 200 mana, so you want enough unreserved mana & mana regeneration. Currently, i have 400 unreserved mana and 100 mana regeneration, you want to adjust your clarity level. Personally i have only a level 15 but it's enough.

Staff : This is the most important part, definitively. What you want on a staff is a +2 to fire, and at least 80% spell crit chance. If you want to spend more currency, what you should be looking for : +2fire/+1 all gems, mana regen (but you can craft it with catarina), mana, fire damage (but you will get low value anyway so it's not so cool), spell damage (doesn't help the burning damage so not that great).
Chest : Get a rare one with as much ES(300+) as possible. If possible, get 2 resistance (including the one you can craft), at least 25%.
Boots : We need The Blood dance : for the regen, and the dexterity is quite valuable (we need 94 for fire trap 20, and our tree doesn't give much). If you can, get a corrupted +1 frenzy charge.
Gloves : You can either get Maligaro's virtuosity or, if you have enough mana / mana regen, Voidbringer.
Helmet : Get a rare one with as much ES(700+) as possible. If possible, get 2 resistance (including the one you can craft), at least 25%.
Rings / Belt : Cap your resistance with them, that's the most important. After, you need 109 strength (for reduced mana 20), and 94 dexterity (for fire trap 20). After that, get some (flat) ES, and if you can get a 15+% max ES on rings (elreon craft). If you have enough currency, get implicit crit chance (diamond ring).
Amulet : If you can, get all your resistance capped without the amulet, so you can get crit multiplier / mana regeneration. You also need a good %max ES prefix, and luxury mod is %crit chance.

Firetrap :
5L : firetrap - empower - fire penetration - elemental proliferation - increased critical strikes
I don't think this is really good with only a 4L, since everything is pretty much mandatory ; empower gives us a high level firetrap, fire penetration is a HUGE damage boost (especially since we have 10% trap penetration from the tree), elemental proliferation is mandatory (see "how this build works"), and increased critical strikes because fire trap base crit is fairly low
For a 6link, i'm not exactly sure of what you can add, probably increased critical damage/increased area of effect / increased burning damage
Flame surge :
4L : flame surge - fire penetration - concentrated effect - trap
5L : flame surge - fire penetration - concentrated effect - trap - increased critical damage/strikes
6L : flame surge - fire penetration - concentrated effect - trap - increased critical damage - increased critical strikes
Helps us against boss / rare, because they are always burning (either fire trap ignite or fire trap burning ground). 4L is enough, 5L is a luxury, 6L is pretty useless imo
Others gems :
You want a CWDT, but a 4R is super expensive because we have only pure intelligence or dexterity gear :( a 3R is still good to reduce high damage spike (as long as it's not 1 hit but CWDT can't help for that anyway).
For aura, you want clarity + discipline. See the mana part for more info.
You need blood rage, assassin's mark to generate your frenzy charge / power charge.
For curse immune maps, you also need a ice spear - power charge on critical - greater multiples projectiles to generate power charge. You can link it with a low level CWDT, but it can be a little tricky to chrome it (it will probably end in your boots, and if you have corrupted one it cost a LOT of vaals to change colors since you want 3 offcolor)
Vaal discipline is useful in dangerous situation where you are low ES and can't run, grab one if you can.


Gem level / quality :

In an ideal world, you want all your gems level 20 and with 20 quality, but sadly it's not an ideal world :P
The most important leveled gem to get is (in this order) fire trap, empower, flame surge, assassin's mark (quality is super good too here), power charge on critical (same here, get as much quality as possible), reduced mana, discipline.

I'm not a good user of flasks (i tend to forget to use them), so i don't find them super impactful. You will need a topaz/ruby/sapphire/quicksilver, with at least 1 "of heat" (you will get frozen very often) and 1 "of stauching" (corrupting blood isn't an issue, but puncture mob will DESTROY you). Get a quicksilver of adrenaline if possible, and also a granite of iron skin.