Unconstrained | D4 Barbarian Key Passive

Unconstrained is a Barbarian Key Passive with the following effect (simplified):
Increase Berserk's maximum duration by 5s and increase its damage bonus by 25%.

Once you select Unconstrained as your Key Passive, you can't select any other Barbarian 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 Unconstrained

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

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

Unconstrained Core Synergies

TBA: When choosing Unconstrained, 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 Barbarian Class.
• Related Skill Tree Nodes: Unconstrained
• Summary of all D4 Build and Character Customization Systems.