Borderlands/Warframe cards

Nekros: Maliwan Plague/Crux - "Bring out your dead!"
Saryn: Maliwan Defiler - "Give sick."
Stalker: Vladof Stalker - "You can run, but you can't hide."
Harrow: Atlas Troll - "Pain Heals."
Valkyr: Dahl Wildcat: "The ultimate close-quarters feline." (also could be Khora/Venari)
Volt: Torgue Rolling Thunder - "The thunder shall bring forth the pain!", or Eridian Thunderstorm - "Lightning never strikes the same place twice, but it can strike freaking everywhere!"
Nova Prime: Maliwan Supernova (from The Pre-Sequel) "More energetic than your average nova."
Mesa: Bone Shredder - "The lead wind blows!"
Ember: The Roaster - "Gonna cook someone today."
Hydroid: Jolly Roger - "A pirate's life for me!"
Nyx: Kitten - "We're all mad here. I'm mad. You're mad."
Titania: The Bee - "Float like a butterfly..."
Mag: Vladof Meganade - "Suck! Suck! Suck!"
Oberon: Landscaper - "Get off my lawn!" (already suggested in comments somewhere)
Atlas: Legendary Berserker class mod - "Never look at my fist."
Nidus: The Hornet - "Fear the swarm!"
Inaros: Sledge's Shotgun - "The Legend Lives"
Garuda: The Meat Grinder - "War is in your blood."