He offered his view on what energy shields could look like in UE-powered Halo, showing off some "flashy shaders" and VFX. They glow, they bounce, and they make you want to play Halo anew.
While we'll have to wait to see if it's close to what the developers have in mind, you can create the effects yourself thanks to Sullivan's breakdown. Interestingly, the VFX is made of basic burst emitter particles, but together with other parameters, they turn into an impressive setup.
Sullivan has many other grand ideas, like the see-through-walls effect from Baldur's Gate 3 he recently recreated in UE.