Khans of Tarkir Seeded Prerelease Booster Mardu has no variants:
Explore this pack in Sealed.

Sheets

Sheet common

At rate 1/33 (3.03%)
Act of Treason
Alabaster Kirin
Arrow Storm
Bitter Revelation
Bring Low
Canyon Lurkers
Debilitating Injury
Defiant Strike
Dutiful Return
Erase
Feat of Resistance
Firehoof Cavalry
Kill Shot
Mardu Banner
Mardu Hateblade
Mardu Hordechief
Mardu Skullhunter
Mardu Warshrieker
Molting Snakeskin
Ponyback Brigade
Rakshasa's Secret
Rite of the Serpent
Rotting Mastodon
Rush of Battle
Shatter
Siegecraft
Smite the Monstrous
Summit Prowler
Swift Kick
Throttle
Tormenting Voice
Trumpet Blast
Valley Dasher

Sheet uncommon

At rate 1/23 (4.35%)
Arc Lightning
Bellowing Saddlebrute
Brave the Sands
Burn Away
Chief of the Edge
Despise
Goblinslide
Gurmag Swiftwing
Horde Ambusher
Hordeling Outburst
Mardu Blazebringer
Mardu Charm
Mardu Heart-Piercer
Mardu Roughrider
Nomad Outpost
Raiders' Spoils
Ride Down
Suspension Field
Swarm of Bloodflies
Take Up Arms
Timely Hordemate
Venerable Lammasu
War-Name Aspirant

Sheet promo

At rate 2/17 (11.76%)
Ankle Shanker
Bloodsoaked Champion
Butcher of the Horde
Crackling Doom
Deflecting Palm
Jeering Instigator
Mardu Ascendancy
Utter End
At rate 1/17 (5.88%)
Zurgo Helmsmasher