38 cards where the full Oracle text includes “wither”

Blazethorn Scarecrow (Shadowmoor #246)
Blight Sickle (Shadowmoor #247)
Boggart Ram-Gang (Shadowmoor #203)
Cinderbones (Shadowmoor #59)
Corrosive Mentor (Shadowmoor #61)
Duergar Cave-Guard (Eventide #51)
Everlasting Torment (Commander 2016 #233)
Fang Skulkin (Eventide #168)
Fists of the Demigod (Shadowmoor #187)
Harvest Gwyllion (Eventide #90)
Hateflayer (Eventide #55)
Inescapable Brute (Shadowmoor #95)
Juvenile Gloomwidow (Shadowmoor #121)
Kulrath Knight (Shadowmoor #190)
Lockjaw Snapper (Shadowmoor #255)
Massacre Girl, Known Killer (Murders at Karlov Manor #94)
Midnight Banshee (Modern Masters 2015 #86)
Necroskitter (Modern Masters 2015 #88)
Needle Specter (Eventide #39)
Noxious Hatchling (Eventide #124)
Oona's Gatewarden (Shadowmoor #173)
Puncture Blast (Eventide #60)
Rendclaw Trow (Eventide #127)
Rustrazor Butcher (Shadowmoor #105)
Scuzzback Scrapper (Shadowmoor #217)
Sickle Ripper (Modern Masters 2015 #96)
Slinking Giant (Shadowmoor #106)
Smoldering Butcher (Eventide #42)
Stigma Lasher (Eventide #62)
Thornwatch Scarecrow (Shadowmoor #265)
Tower Above (Shadowmoor #131)
Twinblade Slasher (Eventide #79)
Wildslayer Elves (Shadowmoor #133)
Witherbloom Campus (Strixhaven: School of Mages #275)
Withering Hex (Onslaught #181)
Withering Wisps (Masters Edition II #114)
Witherscale Wurm (Shadowmoor #134)
Woodlurker Mimic (Eventide #130)

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