How do I stun unstoppable Champions?

[foggy bear]

I am currently running nightfall for challenges but I need something to stun the champions, is there something simple and easy to get that I can use to stun them?

[quaint lily]

Unstoppable Scout rifle is in the artifact mod. If you unlock it, aiming down sights with any scout rifle for a few second will let them stun.

[unborn lava]

when you open your inventory, next to your weapons, each of the anti-champion capabilities should be there.

the subclass keyword anti-champion effects as well as the artifact mods you have.