Madness works independently of why you're discarding the card
except none of those is serious enough for what I would assume your purposes are, I'm afraid: Lowland Oaf Ravenous Giant Another card that might fit better is Nissa's Defeat, which seems to fit halfway on both the visual and "Pause, surrender, letting go, new perspectives" angle (although of course, Nissa would be a "hanged woman")
Knuckles the Echidna Commander Decklist Echidna Echinacea View on Archidekt Commander (1) 1 Knuckles the EchidnaKnuckles the Echidna Creatures (18) 1 Academy ManufactorAcademy Manufactor 1 Ancient Copper DragonAncient Copper Dragon 1 AngerAnger 1 Bonehoard DracosaurBonehoard Dracosaur 1 Daretti, Rocketeer EngineerDaretti, Rocketeer Engineer 1 Glin, Dwarf EmissaryGlin, Dwarf Emissary 1 Goblin EngineerGoblin Engineer 1 Goblin MatronGoblin Matron 1 Goblin WelderGoblin Welder 1 Goldlust TriadGoldlust Triad 1 Goldspan DragonGoldspan Dragon 1 Grenzo, Havoc RaiserGrenzo, Havoc Raiser 1 Hellkite TyrantHellkite Tyrant 1 Magda, Brazen OutlawMagda, Brazen Outlaw 1 Professional Face-BreakerProfessional Face-Breaker 1 Ragavan, Nimble PilfererRagavan, Nimble Pilferer 1 Treasure NabberTreasure Nabber 1 XornXorn Instants (6) 1 Big ScoreBig Score 1 Chaos WarpChaos Warp 1 Final FortuneFinal Fortune 1 Seething SongSeething Song 1 Unexpected WindfallUnexpected Windfall 1 Valakut Awakening // Valakut StoneforgeValakut Awakening // Valakut Stoneforge Sorceries (11) 1 Blasphemous ActBlasphemous Act 1 Brass's BountyBrass's Bounty 1 Hell to PayHell to Pay 1 Hit the Mother LodeHit the Mother Lode 1 Last ChanceLast Chance 1 Reckless HandlingReckless Handling 1 Scrap MasteryScrap Mastery 1 Song of TotentanzSong of Totentanz 1 Strike It RichStrike It Rich 1 Trash for TreasureTrash for Treasure 1 Warrior's OathWarrior's Oath Artifacts (20) 1 Arcane SignetArcane Signet 1 Clock of OmensClock of Omens 1 Cursed MirrorCursed Mirror 1 Everflowing ChaliceEverflowing Chalice 1 Expedition MapExpedition Map 1 Fellwar StoneFellwar Stone 1 Fire DiamondFire Diamond 1 Krark-Clan IronworksKrark-Clan Ironworks 1 Liquimetal TorqueLiquimetal Torque 1 Lotus PetalLotus Petal 1 Mind StoneMind Stone 1 Mycosynth LatticeMycosynth Lattice 1 Phial of GaladrielPhial of Galadriel 1 Planar AtlasPlanar Atlas 1 Prismatic LensPrismatic Lens 1 Ruby MedallionRuby Medallion 1 Sol RingSol Ring 1 Star CompassStar Compass 1 The Reaver CleaverThe Reaver Cleaver 1 Thought VesselThought Vessel Enchantments (4) 1 Descent into AvernusDescent into Avernus 1 Fable of the Mirror-Breaker // Reflection of Kiki-JikiFable of the Mirror-Breaker // Reflection of Kiki-Jiki 1 Guild ArtisanGuild Artisan 1 Spiteful BanditrySpiteful Banditry Planeswalkers (5) 1 Chandra, Spark HunterChandra, Spark Hunter 1 Chandra, Torch of DefianceChandra, Torch of Defiance 1 Daretti, Scrap SavantDaretti, Scrap Savant 1 Karn, Scion of UrzaKarn, Scion of Urza 1 Koth, Fire of ResistanceKoth, Fire of Resistance Lands (35) 1 Arena of GloryArena of Glory 1 Buried RuinBuried Ruin 1 Darksteel CitadelDarksteel Citadel 1 Fomori VaultFomori Vault 1 FountainportFountainport 1 Great FurnaceGreat Furnace 1 Inventors' FairInventors' Fair 1 Mines of MoriaMines of Moria 19 MountainMountain 1 Power DepotPower Depot 1 Scene of the CrimeScene of the Crime 1 Sunken CitadelSunken Citadel 1 The Mycosynth GardensThe Mycosynth Gardens 1 Treasure VaultTreasure Vault 1 Urza's CaveUrza's Cave 1 Urza's SagaUrza's Saga 1 War RoomWar Room Conclusion Thanks for taking the time to read this deck tech on Knuckles the EchidnaKnuckles the Echidna
Fade Away Near Mint - English 1 | $0.99 + Add Fade Away Moderately Played - English 5 | $0.79 + Add Fascination Near Mint - English 4 | $0.49 + Add Fascination Moderately Played - English 1 | $0.39 + Add Fascination Slightly Played - English 3 | $0.44 + Add Floodbringer Near Mint - English 4 | $0.25 + Add Floodbringer Slightly Played - English 4 | $0.23 + Add Floodchaser Near Mint - English 4 | $0.25 + Add Foil Slightly Played - English 7 | $26.99 + Add Foil Moderately Played - English 3 | $23.99 + Add Foil Heavily Played - English 2 | $20.99 + Add Frost Raptor Near Mint - English 4 | $0.25 + Add Graveyard Busybody Near Mint - English 2 | $0.99 + Add Greater Morphling Slightly Played - English 1 | $2.69 + Add Halt Order Near Mint - English 4 | $0.49 + Add Hinterland Drake Near Mint - English 4 | $0.25 + Add Illuminated Wings FOIL - Moderately Played - English 1 | $2.39 + Add Illuminated Wings Moderately Played - English 5 | $0.20 + Add Illuminated Wings Slightly Played - English 3 | $0.23 + Add Impostor Syndrome Near Mint - English 8 | $9.99 + Add
PIKACHU | 2023 POKEMON JAPANESE SV2a-POKEMON CARD 151 173 | ART RARE | PSA MINT 9 $50.00USD Pickup available at Atlanta - Retail 3101 Cobb Parkway Southeast Atlanta, Georgia 30339 Usually ready in 24 hours View store information PSA Graded Card - Certification #161572745 - Grade: MINT 9 Player: PIKACHU
