Iron as it is right now is a perfect clan in terms of Chakra consumption, Offense, and Defense. They can't be approached, can't be ran from, and do extremely high damage, comparable to Uchihas, not to mention healing themselves to increase survivability and denying opponents the ability to use jutsu.
Case in point: Toxic Shock. If you hit an opponent with poison (Iron Sand Rain, Scattered Showers, Corruption talent) you can silence and stun them. Want to use a defensive ability to absorb damage the Iron deals to you? Silenced for 3 sec due to Numbness, then slowed. Good luck escaping the oncoming Iron. This ability has roughly screenwide activation range, as long as the target(s) in question is/are poisoned.
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Someone getting all up in your grill? Iron Sand Rain. You slow them, poison them, and magnetize them to hit them with your other Jutsu in a large AOE. Not much damage you say? Enter Exhibit A and B:
A. Blood to Metal - While using Iron Sand Rain, use 1% of your current health per second to deal 150/200/250% of that damage to the enemy.
and in case they decide to burst you down (you can still use jutsu while Iron Sand Rain is up),
Exhibit B. Iron Blood - While using Iron Rain, increase defense by 10/20/30/40% and regenerate 0.5/1/1.5/2% of your missing health per second.
Take note that this passive is in fact a straight upgrade from Kaguya's Bone Golem (in comparison), which with 3 skill points offers 30% defense, and raises your regen to 40 (Iron's regen continues going in addition to the 2% from Iron Sand Rain).
Still think 40% Defense isn't much ontop of the regen?
SURPRISE! Exhibit C: Aegis - You gain 10/20/30% defense while using golden sand.
Now not only does it do 40% more damage, you gain 40% defense, then 30% on top of it for the entirety of the duration!
As a result, Iron Sand users are NOT killable during this skill. It's like fucking Uchiha Vengeance on a lower cooldown and twice the duration while dealing a significant amount of damage in an AOE, poisoning, and slowing.
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Cluster is a high damage nuke. The damage is somewhat avoidable if you're able to use a defensive jutsu before it hits. However, any Iron worth their salt can stack stacks of poison on you and then Toxic Shock you so you can't defend yourself and force you to take the full damage (often 1/3 of my hp as a Kaguya with 30 Stam and 30 Str and under 10 levels to level cap). Also, guess what, since the area is small enough, Irons can hit you with Iron Sand Rain while you're INSIDE the cluster!
Hell, if you land one tile outside of the cluster, you get stuck in the spikes and anyone can wail on you for the full duration.
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Now let's talk about Unleash. After the skill's duration (which is ludicrously long) the opponent has maybe 20 seconds until they can use it again. 'Don't run into the spikes you nub', you say? The spike positions aren't exactly made clear from the point of view of the player, the Iron user is free to wail on you while you're in it, and you get poisoned, magnetized, and stunned if you touch one. This ability puts Seedling Ferns to SHAME. You can at least Sub out of Ferns, but if you try to Sub out of Unleash and hit a spike? STUNNED, STOPPED, POISONED, SLOWED. You have to carefully maneuver your way around the spikes while the Iron Sand user is spamming at you, wandering freely in the spikes, which WILL come out of nowhere because:
EXHIBIT D: Grand Unleash - Your iron sand unleash deals 10/20/30% more damage and has 33/66/100% less charging time. The slow magnitude is also increased. Oh yeah, Golden Sand makes this even more fun to be inside.
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But Suspicious, no one can just spam these skills forever, right? Just let them spam and then kill them!
WRONG.
EXHIBIT E: Chakra Flow - +50/100/150% chakra regeneration. AND Corruption - Every 40/25/10 seconds, your next poison applying jutsu instantly applies 5 stacks of poison and your chakra regeneration is increased by 10 per seconds for 10 seconds.
GEE, I WONDER HOW HARD IT IS TO APPLY POISON AS SOMEONE WITH GIGANTIC, POISON APPLYING AOES AND PROJECTILES
Long story short, this clan has risk-less sustain, impressive chakra regen, better damage scaling than an Uchiha (seriously just look at the first damage talent for Uchiha and compare it to Iron's. Spoiler: Iron's is better), easily acquired, long-lasting, and multi-utility defense, and a package of skills set to badly disable anyone you hit. It needs a nerf. Badly. Doubling the cooldown on Rain didn't do enough.