[2.4] Blast Rain (pure fire & max aoe guide)

OVERVIEW:
[+] King of AoE.
[+] Pure fire damage (no need for hybrid ele damage, frees a gem slot for fire penetration).
[+] Great for PVP skirmishes, 3v3 CTF, and very fast for PVE.
[+] Synergy with Herald of Ash that decimates any WormBlaster troll.
[+] Don't need pierce (save a lot of points on passive tree)
[+] Don't need expensive +1 arrow corruptions (hint: they don't work on blast rain)
[-] Natural weakness is obviously 100% fire conversion talismans (but that's why you always have a weapon-swap to pure physical skill to burst down those talisman hot-swappers).


MECHANICS:
[+] There is no new mechanic here. I'm not gonna take credit for things I didn't first come up with.
[+] Blast rain hits 4 times. Total %damage is weak compared to Barrage, but with maximum AoE, you are almost guaranteed to hit your target unlike Barrage. From the PoeWiki: "By default explosions fall in a 20 radius area and may overlap in a 3-unit circle." This overlap zone is enhanced by increased AoE (confirmed by ViperMagi). http://pathofexile.gamepedia.com/Blast_Rain
[+] Mechanic #1: You have your standard broken-OP pathfinder.
[+] Mechanic #2: You add in some Signal Fire quiver for 50% physical to fire conversion.
[+] Mechanic #3: AoE AoE AoE (increased AoE gem + Dying Sun + passive tree)
[+] Mechanic #4: CI OP (mirror my shit gudammit!)


BLAST RAIN (SignalBLAST) VS BARRAGE (SignalShot):
[+] It's not always about tooltip dps. Yes, theoretical dps of Barrage is king. But how many of those arrows actually hit an enemy in sarn? 'Nuff said.
[+] Blast rain has natural 50% conversion. Signal Fire quiver completes the conversion.
[+] Massive 142% increased AoE (12% from uber helm enchant, 45% from AoE gem, 15% from passive tree, and the rest from a quality-20 Blast rain). Once you get this level of AoE superiority, you can offset the delay time of Blast Rain because the explosions are so damn wide.
http://pathofexile.gamepedia.com/Blast_Rain


HERALD OF ASH BECOMES A 7th-link:
[+] This is mainly from the perspective of a Wormblaster. But, Herald of Ash kills the worms faster than the Wormblaster herself. The chain reaction guarantees status-ailment kills, further recharging your flasks.
[+] Quality on the Herald of Ash is a global increased fire damage. The 15% added fire damage bonus complements well with Signal Fire's 35% added fire for a whopping total of 50% added fire. You can even use the Added Fire Damage support gem to reach close to 100% added fire damage. (Did someone say Doomprism on a Broodtwine?)
http://pathofexile.gamepedia.com/Herald_of_Ash


DEFENSE IS OFFENSE:
[+] I previously thought that Rearguard is king, but the Reckless Defence jewels combined with having massive ES pools means that we can actually achieve near-75/75 block without Rearguard. With perfect legacy Rumi (40/20 block) and 3 reckless defence jewels, I reach 74/74 block on flask activation. The caveat is that you have ZERO block without rearguard, as the reckless defence jewels only activate when you have a source of base block chance. (but this is gonna change because I have pretty much decided on my unique design, which will be a Crystal Belt that grants permanent flask effect but disables flask use).
http://pathofexile.gamepedia.com/Reckless_Defence
http://pathofexile.gamepedia.com/Rumi%27s_Concoction


OTHER MISC TRICKS OF UPTODATE PVPers:
[+] CWDT+FROST BOMB. Frost bomb turns all the lifers into CI (75% reduced life regen).
[+] CWDT+projectile weakness+enhance. Because "increased projectile damage taken" applies to blast rain (confirmed by ViperMagi).

GEM SETUP:
G Blast rain
G Block penetration / Faster Attacks
R Added Fire Damage / Critical Strike Chance
R Weapon Elemental Damage
R Fire Penetration
B Increased AoE

GEM SETUP AGAINST 100% FIRE CONVERSION TALISMAN HOT-SWAPPERS:
G Rain of Arrows
G Block penetration / Faster Attacks
G Physical Projectile Attack Damage
B Increased AoE
B Critical Strike Chance
G Point-blank / Faster Projectiles

JEWELS:
Reckless Defence Jewels:
(at a minimum of 3, assuming you have perfect legacy 40/20 rumis).

Rare jewels (optional):
Note: "increased projectile damage" does work on Blast Rain even though the skill gem does not have a "projectile" tag, confirmed by ViperMagi.
https://www.pathofexile.com/forum/view-thread/1497988/page/4#p13779404

PASSIVE TREE:

GEARING:


IGN: AMAZONPRIME

After a week of testing in both pvp and pve, here are some updates guys:

[+] King of the hill knockback definitely reduces dps, pushing the enemy away from the overlap zone, despite increased area of effect.

[+] Elemental penetration really feels weaker without vinktar support. Going pure fire means our only sources of ele pen are from pathfinder's ascendancy, the fire support gem, the boot enchant, and forces of nature. Lava lash is too far on the tree to reach. Perhaps 5% pen from the new essence league belts. But as of right now, I am sitting at only 64% fire pen compared to vinktar/lightning variant of 85%.

[+] However, the lightning variant of blast rain is only 50-70% actual lightning depending on how much conversion you take. Fire variant of blast rain is 100% fire without heavy investment. So, it really comes down to comparing 100% of 64% penetration vs 50-70% of 85% penetration.

(reserved)

Doesn't Inc AOE also increase the possible area of the random blasts? For firestorm, I think someone did a calculation to show that Inc AOE actually decreased your hits because it would also send some fireballs down further away from the center.

absolutely, increasing AoE increases the base 8 unit radius overlap zone.
However, if you use king of the hill, the amount of knockback also increases, and in my experience, pushes the enemies even farther away from the maximum overlap zone.

tl:dr this build sucks without mirrored gear?

^

^

Stephen King's "IT"
https://en.wikipedia.org/wiki/It_(miniseries)

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