Uhtred's Not Working?

Boundless is supportiny coc not comet.

My setup is 2x Vomits - Auguary - Dialla's - Atalui

Im mana. You can see my setup at Ziqelchaos

Boundless Energy is a support gem for Meta/Invocation skills that generate energy, like Cast on Critical, Cast on Elemental Ailments, Elemental Invocation, Spellslinger, etc.

When you put it into Cast on Critical, it is a support gem supporting Cast on Critical.

Dialla's Desire is a lineage support gem that can support any skill gem. It adds +1 level, +10% quality, and 90% cost reservation/efficiency multiplier. It can support any gem, so when you put it into Cast on Critical, it will support both Cast on Critical and any spells you put in it.

Uhtred's Augury gives +3 skill levels to skills that have exactly two other support gems supporting it, not including itself.

Cast on Critical has Boundless Energy and Dialla's Desire supporting it, making it eligible for Uhtred's Augury's +3 levels to apply

Arc and Comet have just Dialla's Desire supporting it, making it ineligible for Uhtred's Augury's +3 levels to apply.

If you want Arc and Comet to get the +3 levels, swap out Uhtred's Augury for Uhtred's Omen. It will give them +3 while not giving CoC +3.

If you want all 3 (CoC, Comet, and Arc) to get +3, you will need to replace Boundless Energy with something that can support everything, or replace Arc or Comet with a support gem that supports one or the other. For example, replacing Arc with Spell Cascade or Efficiency 2.

TL;DR: Boundless only supports CoC because CoC generates energy. Dialla's supports everything. Comet and Arc aren't getting +3 because only Dialla's is supporting it.

Only Dialla's is supporting your comet

They probably have lifetap or atalui and you didn't notice

My setup allows augury to buff both

Rakiata, Augury, Dialla, boundless energy

Swop arc with atalui

Replace Arc with a support gem for Comet