So what does Force do?

[noncom]

For now the only effect that I've noticed and clearly understood is that it forces me to go play something else.

[Eldritch Warden]

Force is the catch all for the miscellany. For duration based abilities it increases the duration. For projectiles that can pierce, it's pierce (like the archer's arrows). I am not sure if there's any other function, but those are 2.

[noncom]

So it's like "It does everything that needs to be done, just pick it because it's the best choice so you don't need to even think" ? I mean unless I want something like healing or speed.

[Back from Earth]

yeah, it's impossible for me to evaluate Force when the game doesn't even tell me what it's doing

[Eldritch Warden]

It's more of a "utility" pick. You want damage for your phantom needles. sure, but you also want coverage. In this case, the piercing will exponentially increase the effectiveness of one of the evolutions of this weapon. Channelling may also help give you more leeway when picking traits for said weapon. More dps and less piercing from the weapon traits because channelling can help with that a bit.

[Ulyaoth]

Its just addet two traits in one, that what @Eldritch Warden said and gives Knockback to Melee attacks, maybe Beast Huntress Spear as well, it seems like so.

So Summon Lifetime, Rollduration of Golem, Lifetime of some other Projectiles e.g. Kugelblitz.
Piercing for some projectiles.
Its the same what you would picked probalby before, when doing some builds.