Strength

[Growing Power]

This does require an aura forma but hey, that's what they're for.
Proc' status before casting spores and you touch 200 power strength. Pickup an energy orb and you hit 250.

[Energy Conversion] vs. [Transient Fortitude]

I run Naramon, so most of my energy comes from orbs, which makes [Energy Conversion] viable for replacing [Transient Fortitude].

[Energy Conversion] provides 5% more power strength than a fully ranked [Transient Fortitude] without the duration penalty, but if you don't like the conditionals then swap for Transient Fortitude.

Flexibility

• You have two option slots, slot 2 and the exilus slot.
• Only needs five points to max out [Blind Rage] and the two Umbral mods.

Forma cost

I used umbral forma to fit with my config B, forma as you see fit.