Some fantasy slurs and terms I have come to love... feel free to add more!
Garden Gnome: Forest Gnome who spends too much time in the city, rock gnome who spends too much time in the woods
Leprechaun: Brownie who worships Deliar
Quarterling: Brownie or short halfling
Knife Ears: Elf (from dragon age)
Turnipmonger: Gnome
Gutter Gnome: Goblin or uncouth halfling
Civie: those who live in cities
Grubber: Goblin
Spiderkisser: Dark Elf
Baby Muncher: Gobbo, Giantkin, Orc
Stink Elf: Wood or Wild Elf
Halfer: halfling or halfblood
Tiefer: Tiefling
Spawnbaby: Tiefling
Gremlin: Inventor Goblin or Mischevous Gnome
Gremlock: trapsmithing gremlin
Daisy Eater: elf
Stunty: dwarf
Pigface: Orcblood
Smoothface: elfblood or human who shaves
Smoothskin: greenskin term for the common races
Pinkskin: same as above, but omitting deep races
Greenskin: orc or gobbo
Bearded Gnome: Dwarf
Forgefarter: obese crafting Dwarf
Demon Dwarf: term used by Grandites as an alternative to "he who shall not be named"
Blood Dwarf: Term used by orcs for Voraxian zealots
Stumpy: dwarven slur against Grand
Stumpslingers: Grandite Priests
War Singer: goblin, orc or giant bard
Rockbiter: giantkin
Lichleech/leechlich: vampire
Dwarfpet: forging human
Trog: orc, goblin, troll, giant
Treehugger/tree worshipper: nature elf or druid
Pie-Goblin: Halfling
Bum Nibbler: Gnome, halfling or goblin
Frogstomper: sea elves or those with webbed toes like some kinda fishboy
Spellsinger: bard
Gortsmorfer: a ravenous gnome who viciously assaults snack trays at social functions. There is no such term for halflings, as such is already expected of them
Gremlock: Deep gnome with low charisma
Goober: goblin
Boogergnome: goblin
Bloodbaby: generation directly following the fall of Bloodstone and the initial strife of the dark ages. They get together, drink and talk of the olden times before all these spoiled wee whippersnappers when they had to walk uphill both ways over the still warm bodies of demons to get a good scotch, and it was always out of stock.
Lichlover: necromancer
Guildbaby: 2nd generation guildsman
Snotling: Goblin
Dockporker: Half-Orc kicked out of Hempstead
Mole King: Gnome Druid
Rotmugger: Greenskin, or very ugly
Wrist-Fisher: pirate with a hook
Cyclops: one-eyed man
Griffonguts: a poor fool too brave to know when to stop drinking
Fishboy: sea elf