34 cards where the cards have the “silumgar” watermark

Acid-Spewer Dragon (Dragons of Tarkir #86)
Deathbringer Regent (Dragons of Tarkir #96)
Dragonlord Silumgar (Dragons of Tarkir #220)
Dutiful Attendant (Dragons of Tarkir #99)
Grim Haruspex (The List #UGIN-73)
Gurmag Drowner (Dragons of Tarkir #57)
Hand of Silumgar (Dragons of Tarkir #105)
Marang River Skeleton (Dragons of Tarkir #108)
Minister of Pain (Dragons of Tarkir #111)
Necromaster Dragon (Dragons of Tarkir #226)
Noxious Dragon (Fate Reforged #77)
Palace Familiar (Dragons of Tarkir #69)
Profaner of the Dead (Dragons of Tarkir #70)
Qarsi Deceiver (Dragons of Tarkir #71)
Qarsi Sadist (Dragons of Tarkir #113)
Rakshasa Gravecaller (Dragons of Tarkir #114)
Risen Executioner (Dragons of Tarkir #116)
Ruthless Deathfang (Dragons of Tarkir #229)
Ruthless Ripper (Magic Online Promos #55767)
Shambling Goblin (Dragons of Tarkir #118)
Sibsig Icebreakers (Dragons of Tarkir #119)
Sidisi's Faithful (Dragons of Tarkir #74)
Sidisi, Undead Vizier (Dragons of Tarkir #120)
Silumgar Assassin (Dragons of Tarkir #121)
Silumgar Butcher (Dragons of Tarkir #122)
Silumgar Monument (Dragons of Tarkir #243)
Silumgar's Command (Dragons of Tarkir #232)
Silumgar Sorcerer (Dragons of Tarkir #76)
Silumgar Spell-Eater (Dragons of Tarkir #77)
Silumgar's Scorn (Dragons of Tarkir #78)
Silumgar, the Drifting Death (Fate Reforged #157)
Vulturous Aven (Dragons of Tarkir #126)
Wandering Tombshell (Dragons of Tarkir #127)
Youthful Scholar (Dragons of Tarkir #84)

The message was clear to Sorin—time to search for something else.