Esu's Ferocity | D4 Sorcerer Key Passive

Esu's Ferocity is a Sorcerer Key Passive with the following effect (simplified):
Your Fire Critical Strike Damage is increased by 25% against enemies above 50% Life. Your Fire

Once you select Esu's Ferocity as your Key Passive, you can't select any other Sorcerer Key Passive. They're considered to be very important parts of your build, so it merits quite a bit of possible discussion.

How best to use Esu's Ferocity

Basically this segment will be giving you a rundown on the basics on the "WHEN, HOW, and WHY" of the Esu's Ferocity Key Passive.

Questions we would answer here would be like:
How to use Esu's Ferocity, as a baseline.
Why you would choose Esu's Ferocity over other Key Passives.
When would you consider Esu's Ferocity? As a build-around? An "augmentation"?

Esu's Ferocity Core Synergies

TBA: When choosing Esu's Ferocity, are there "absolute godtier" level synergies you essentially NEED to take?

Related Links & Other Information

Still got a lot to do, a lot of data to track, and how best to present it! Post-launch will clarify alot of this for us!

In the meantime, Related Links:

• If you're here, you're probably looking for some info on the Sorcerer Class.
• Related Skill Tree Nodes: Esu's Ferocity
• Summary of all D4 Build and Character Customization Systems.