This deck relies on getting a turn 1-2 unblockable creature out, then immediately getting Yuriko out. This deck accrues value through dealing damage to opponents with unblockable creatures, and the effects that they have. This deck is capable of a couple of good strategies, and playing to your outs is simple.
Slow burn. This is mainly for when your hand is pretty dead. Just keep dealing damage, and when you get a transmute card for 3, but don't feel safe tutoring for doomsday to win, tutor for Arcane Adaption to accrue more value from your unblockable boys.
Doomsday - Unearth Pile. This is the classic budget Doomsday pile that goes in every budget doomsday deck This is not special, or cool, but damn does it get the job done. Git Probe -> Predict -> Lab Maniac -> Unearth -> Street Wraith

You draw Git Probe off of a Yuriko attack trigger, target the person you think might have counterspells to see what you're up against, then draw and subsequently cast Predict, naming Laboratory Maniac. After that, unearth Lab Man and cycle the wraith to win. It's a 1UB pile if you have 5 life. It's a 1UUB if you have 3 life. It doesn't work if you have 2 or less life.

3. Doomsday - Yuriko, High Noonsday Pile. The namesake of the deck, this pile is an interesting one, yet probably the safer option if you're facing a barrage of counterspells. They'll usually let Doomsday resolve so you lose after they counter your win con. If you know you're facing counterspells, or have the suspicion, pick this pile instead. Worst case scenario, they counter your Doomsday and you revert to the Slow Burn method.

Here's how it works. If you have 5 or more ninjas, this pile will work perfectly. Set it up like this : Draco -> Inkwell Leviathan -> Elder Deep Fiend -> Distended Mindbender -> Treasure CruiseWith this, you will kill everyone at the table other than you. If you reveal all 5 with ninjas, you win. The total CMC of all those cards is 49. IF you only have 2-3 ninjas out, the pile becomes a little less brain-dead to set up. Let's say you only have two ninjas on board, but you can attack someone with them. You would pile Draco -> Karn's Temporal Sundering -> (Applicable Response such as Misdirection, Counterspell, etc) -> Inkwell Leviathan -> Elder Deep Fiend. With this, you swing with your two ninjas, dealing 22 damage. Then, you cast Karn's Temporal Sundering, taking an extra turn and bouncing something. Then, you draw whatever Response card you need, like Counterspell. After that, you just swing again and win the game!

Note: Something I've realized is smart, is if you're worried of your opponents making you draw on your extra turn, is to put Laboratory Maniac as the third card in the pile. Super corner case, but worth it if you need to pass the turn with no cards in deck.

https://www.reddit.com/r/BudgetBrews/comments/b8z6wd/contest_75_yuriko_high_noonsday_improved_ultimate/