[Mod too weak: Health Conversion]

This mod is crazy good on frame with ability scaling on armor, namely Nezha, Rhino and Frost.

-You don't loose stack upon getting hit while Iron Skin / Warding Halo is active

-Those ability scales with armor

So basically, cast IS/WH, get your 3 stacks, deactivate and recast to reapply ability with modified armor

On those frame, this mod acts like a Steel Fiber upgrade, and gets you crazy amount of EHP

Spoiler

Nezha's Warding Halo

Max power strength, max Health Conversion
Modified Health = ((900*2.99) + (2.5*2.99) × (175+1350)) × 2.99 = (2691 + 7.475 × 1525) × 2.99 = 42 130 HP

Max power strength, max Steel Fiber
Modified Health = ((900*2.99) + (2.5*2.99) × (175+192) × 2.99 = (2691 + 7.475 × 367) × 2.99 = 16 250 HP

Formula is from the wiki

Still I agree this is too specific, and close to useless on other frames. The shield damage removing stacks is really dumb....