Yuriko Bounce (EDH / Commander)

'Yuriko, the Tiger's Shadow' leads a deck that lets you attack often and often with impunity. The strategy includes economical, unblockable creatures to set-up ninjutsu targets and cards to manipulate the top card of your library to ensure splashy, heavily mana costed pay-offs on Yuriko's ability.

This build emphasizes global bounce effects over slotting in spot removal. Run the engine as long as possible, then reset the board as required to buy time and get ninja's back to hand - rinse and repeat. Man-land includes 'Mutavault', 'Creeping Tar Pit' and 'Faerie Conclave' survive the bounce, providing instant attackers to get ninja's back on the offensive quickly.

Big plays may include Insidious Dreams to set up a barrage of damage - cast in response if several ninja's are set to get through. Vorpal Sword acts as single player removal.

Ninjutsu Fuel. Includes extra utility, flash and haste where possible:

Baleful Strix - Flying, deathtouch, card draw.
Thalakos Seer - Shadow, draw 1 when leaving battlefield (after ninjutsu).
Ornithopter - 0 cost, flying.
Ornithopter of Paradise - Flying, ramp.
Thousand-Faced Shadow - 1 cost, flying, ninja.
Faerie Impostor - 1 cost, flying, bounce a ninja to hand upon ETB.
Quickling - Flash, flying, bounce a ninja to hand upon ETB.
Spellstutter Sprite - Flash, flying, counter upon ETB.
Hypnotic Sprite // Mesmeric Glare - Flying or counterspell.
Triton Shorestalker - 1 cost, unblockable.
Mist-Cloaked Herald - 1 cost, unblockable.
Slither Blade - 1 cost, unblockable.
Gudul Lurker - 1 cost, unblockable.
Changeling Outcast - 1 cost, unblockable, ninja.
Nether Traitor - Unblockable, haste, recur-able.
Tormented Soul - 1 cost, unblockable.
Spectral Sailor - 1 cost, Flash, flying, card draw.
Phantom Ninja - Unblockable, ninja.
Kaito Shizuki - -2 creates a 1/1 unblockable ninja.

Getting Through. Once they're on the battlefield, make your ninja's unblockable.

Alora, Merry Thief - When you attack, one creature becomes unblockable, then returns to hand (Ninja reload).
Krydle of Baldur's Gate - 2:make an attacker unblockable, scry 1 on combat damage.
Tetsuko Umezawa, Fugitive - Any of your creatures with 1 power or toughness is unblockable.
Thassa, God of the Sea - 1U: Target creature is unblockable this turn.

Stack the Deck. Find answers, put big mana values on top for Yuriko to count:

Brainstone
Conch Horn
Sensei's Divining Top
Brainstorm
Lim-Dûl's Vault
Insidious Dreams
Scheming Symmetry - Use with Opposition agent for the lulz.
Varragoth, Bloodsky Sire

Notes

Bounce multi-tools 'Quickling', 'Cryptic Command', 'Faerie Impostor' and 'Familiar's Ruse' among others can be used to reload Ninja's back to hand or to clear defenders along with providing other utility. Permanents 'Equilibrium', 'Crystal Shard' or 'Sanctum of Eternity' can be used to similar effect.

Make all of your creatures count toward Yuriko's ninja trigger using 'Conspiracy' and/or 'Maskwood Nexus'.

Higher casting cost spell options offering alternative forms of casting payment were chosen to max Yuriko's damage effect, but leave them realistically castable. Mechanics such as Delve: 'Treasure Cruise', 'Temporal Trespass', 'Dig Through Time'; Miracle: 'Devastation Tide', 'Temporal Mastery'; Undaunted: 'Coastal Breach'; Exile from hand: 'Force of Negation', 'Misdirection', 'Commandeer'; Commander on field: 'Fierce Guardianship'; Foretell: 'Spectral Deluge, Saw it Coming, Alrund's Epiphany', etc.

Rather than use card slots for unlimited hand-size to accommodate Yuriko's draw power, discard instead provides currency to pay alternative costs of many cards (Delve, Exile from hand, Buyback, etc). The one exception being Sea Gate Restoration // Sea Gate, Reborn as it's high casting cost can be used by Yuriko, with flip side of an additional land playable earlier in the game.

Honourable Mentions

Dimir Infiltrator - Unblockable, tutor.