Hunting Numbers: Best Number Xyz for Umbral Horror

Players built OTKs around Utopia Double a long time ago. In Umbral Horror it has a new job: it brings out Number 99: Utopia Dragonar and sets up your board. Utopia Double reads:

(Quick Effect): You can detach 1 material from this card; add 1 "Double or Nothing!" from your Deck to your hand, then Special Summon from your Extra Deck, 1 "Utopia" Xyz Monster, except "Number 39: Utopia Double", by using this face-up card you control as material, and if you do, its ATK becomes doubled, but it cannot attack directly. (This is treated as an Xyz Summon. Transfer its materials to the Summoned monster.) You can only use this effect of "Number 39: Utopia Double" once per turn.

Dragonar lands with 2 materials: Utopia Double itself and the material Double kept. Detach both and Dragonar Special Summons any Number from 1 to 100 out of your Extra Deck, Number C monsters such as Number C32: Shark Drake LeVeiss included. Both effects are Quick Effects, so you can wait for your opponent to commit and then pick the Number that answers their board.

The Number arrives with no materials. Banish Barian's Hope from your GY to attach a Number from your Extra Deck or GY to it, since Lancelot and Zombiestein need a material before they can negate anything.

Read these Numbers before you add them to your Extra Deck:

Now the Double elephant in the room: Double or Nothing!. Utopia Double can't use its effect without a copy in your Deck, and you will draw that copy at the worst moment. Put it to work anyway. Barian's Seventh Untopia adds an Umbral Horror monster to your hand and then makes you discard, so Double or Nothing! pays that cost. It doubles as the Spell you discard to Xyz Summon Number C32: Shark Drake LeVeiss on top of a Rank 4 Shark Drake. You can also return it back to the deck with Seventh Tachyon.

Add Utopia Rising to your Utopia package. The search on Number 104: Masquerade V is a soft once per turn: each copy can detach a material to add a Barian's Spell or Trap, so a second Masquerade V with materials gets you a second search.

After your combo sends a Masquerade V to the GY, make 2 Level 4 monsters and Xyz Summon Utopia Rising. Rising revives Masquerade V in Defense Position and moves both of its own materials onto it. That buys you one more search: another combo piece, or your Barian's counter, which extends the combo as well.

Run at least one of the two Barian's rank-ups. Rank-Up-Magic Limited Barian's Force needs a Rank 4 Xyz, the Rank your deck makes most, and brings out any Rank 5 Number C. Rank-Up-Magic Barian's Force works from any Rank into a Number C one Rank higher, as long as both monsters share a Type.

Rank up a Rank 4 Number such as Masquerade V into Number C106: Giant Red Hand and it keeps a Number as material, which its negate needs. Barian's Force on Titanic Galaxy, a Rank 8 Dragon, gives you Number C107: Neo Galaxy-Eyes Tachyon Dragon.