48 cards where the color identity ≤ BW and the text includes “whenever a creature” and the text includes “gain” and the text includes “life”

Abattoir Ghoul (Duel Decks: Blessed vs. Cursed #50)
Ajani's Welcome (Core Set 2019 #6)
Angelic Chorus (Battlebond #87)
Angel of Destiny (Zendikar Rising #2)
Anointer Priest (Amonkhet #3)
Answered Prayers (Modern Horizons #2)
Ashes of the Abhorrent (Ixalan #2)
A-Tenured Inkcaster (Strixhaven: School of Mages #A-88)
Authority of the Consuls (Foundations #137)
Bastion of Remembrance (Duskmourn: House of Horror Commander #131)
Battlegrace Angel (Modern Masters 2015 #10)
Bounty Board (Outlaws of Thunder Junction Commander #37)
Campaign of Vengeance (Eldritch Moon #182)
Case of the Uneaten Feast (Murders at Karlov Manor #10)
Curse of the Forsaken (Commander Anthology #8)
Derelict Attic // Widow's Walk (Duskmourn: House of Horror #93)
Dross Harvester (Commander Legends: Battle for Baldur's Gate #750)
Elemental Time Flamingo (Unfinity Sticker Sheets #46)
Funeral Room // Awakening Hall (Duskmourn: House of Horror #100)
Grasping Shadows // Shadows' Lair (The Lost Caverns of Ixalan #108)
Grasping Shadows // Shadows' Lair (The Lost Caverns of Ixalan #108)
Hooded Blightfang (Core Set 2021 #104)
Invasion of Ulgrotha // Grandmother Ravi Sengir (March of the Machine #116)
Invasion of Ulgrotha // Grandmother Ravi Sengir (March of the Machine #116)
Kamber, the Plunderer (Outlaws of Thunder Junction Commander #137)
Kheru Bloodsucker (Khans of Tarkir #75)
MacCready, Lamplight Mayor (Fallout #108)
Moonlit Wake (Mercadian Masques #29)
Moonstone Eulogist (Bloomburrow Commander #19)
Noble Purpose (Eighth Edition #31)
Noble Stand (Nemesis #14)
Ondu Rising (Battle for Zendikar #41)
Patron of the Kitsune (Betrayers of Kamigawa #19)
Perimeter Captain (Worldwake #16)
Profane Memento (Magic 2015 #226)
Proper Burial (Dissension #16)
Relic Vial (Zendikar Rising #250)
Revenge of Ravens (Throne of Eldraine #104)
Righteous Cause (Commander Anthology #21)
Sangromancer (Commander 2021 #152)
Shadows of the Past (Duel Decks: Nissa vs. Ob Nixilis #60)
Soul Net (Seventh Edition #317)
Suture Priest (March of the Machine Commander #210)
Tenured Inkcaster (Outlaws of Thunder Junction Commander #149)
The Meathook Massacre (Innistrad Remastered #122)
Thieving Amalgam (Outlaws of Thunder Junction Commander #150)
Touch of Moonglove (Magic Origins #123)
Trespasser's Curse (Amonkhet #112)
Vein Ripper (Murders at Karlov Manor #110)
Vigil for the Lost (Scars of Mirrodin #26)

Though this query has ended, its relics still slumber in New Argive.