35 cards where (the text includes “die” or the name includes “leaves”) and (the text includes “draw” and the text includes “card” and the text includes “when”) and the card types include “creature” and the colors is U

Chasm Skulker (March of the Machine Commander #218)
Minn, Wily Illusionist (Forgotten Realms Commander #16)
God-Eternal Kefnet (War of the Spark #53)
Cavalier of Gales (Core Set 2020 #52)
The Watcher in the Water (The Lord of the Rings: Tales of Middle-earth #75)
Skystrike Officer (The Brothers' War #62)
Thought Sponge (Commander 2019 #12)
Malcator's Watcher (Phyrexia: All Will Be One #58)
Whirlpool Drake (Apocalypse #34)
Floating-Dream Zubera (Champions of Kamigawa #61)
Jason Bright, Glowing Prophet (Fallout #32)
Oracle of Tragedy (March of the Machine #71)
Inga Rune-Eyes (Commander Masters #100)
Purple-Crystal Crab (Global Series Jiang Yanggu & Mu Yanling #3)
Murder of Crows (Commander Masters #106)
Trove Tracker (Commander Legends #104)
Thopter Mechanic (The Brothers' War #68)
Palace Familiar (Dragons of Tarkir #69)
Jeskai Sage (Fate Reforged #38)
Surveilling Sprite (Duel Decks: Ajani vs. Nicol Bolas #43)
Ithilien Kingfisher (The Lord of the Rings: Tales of Middle-earth #58)
Vexing Sphinx (Dominaria Remastered #73)
Watchful Blisterzoa (Phyrexia: All Will Be One #78)
Oculus (Mirrodin Besieged #29)
Expedition Diviner (Zendikar Rising #57)
Aven Fisher (Dominaria Remastered #41)
Youthful Scholar (Dragons of Tarkir #84)
Exultant Cultist (Eldritch Moon #59)
Darkslick Drake (Scars of Mirrodin #30)
Oculus Whelp (March of the Machine #69)
Runewing (Return to Ravnica #48)
Messenger Drake (Magic 2014 #63)
Kingfisher (Urza's Destiny #36)
Rushing-Tide Zubera (Saviors of Kamigawa #52)
Merfolk Seer (Mirage #76)

This search is finished. Now the real work can begin.