Subjunctive KoL: TattooList

There are currently a total of 77 known generally-obtainable tattoos, though most of them can only be obtained through Ascension. You get outfit-related tattoos from the PretentiousArtist by visiting him while wearing a complete outfit. Ascension-related tattoos are given to you when you open the letter from King Ralph after completing an ascension. Here are the tattoos (ordered in the order in which they're displayed):

• antique helmet -- visit with the AntiqueArms And Armor
• hollow Roman numeral I, II ... XI, XI+ -- complete that number of softcore ascensions (XI+ is for 12 or more)
• black helmet -- visit with the BlackArmaments
• Crimbo light -- visit with the BowTux
• dancing bugbear -- visit with the BugbearCostume
• maple leaf -- visit with the OKLumberjack outfit
• class tattoo (seal club, turtle, pasta spoon, saucepan, disco ball, accordion) -- start an ascension as that class
• sparkly class tattoo -- finish a Hardcore ascension as that class
• extra-sparkly class tattoo -- finish a Hardcore Oxygenarian ascension as that class
• clockwork gear -- visit with the ClockworkApparatus
• scary clown -- visit with the ClownCostume
• Cloaca-Cola can -- visit with the CloacaColaUniform
• Dyspepsi-Cola can -- visit with the DyspepsiColaUniform
• snowflake -- visit with the eXtreme ColdWeather Gear
• Oyster egg -- visit with the GrassGuise
• Elbereth -- visit with the YendorianFinery
• halberd -- visit with the Knob Goblin EliteGuard outfit
• beer can -- visit with the FratBoy Ensemble
• gnauga -- visit with the GnaugaHides
• Knob heart -- visit with the Knob Goblin HaremGirl outfit
• solid Roman numeral I, II ... XI, XI+ -- complete that number of hardcore ascensions (XI+ is for 12 or more)
• peace sign -- visit with the FilthyHippy Disguise
• hourglass -- visit with the TimeTrappings
• jellyfish -- visit with the EncephalicEnsemble
• L -- visit with the FurrySuit
• martini -- drink a number of martinis (it's a random chance you'll get this each time you drink a martini)
• pickaxe and shovel -- visit with the MiningGear
• ninja mask -- visit with the Hot and Cold Running NinjaSuit
• crossed-out booze -- complete a Hardcore Teetotaler ascension
• crossed-out food -- complete a Hardcore Boozetafarian ascension
• oxygen molecule -- complete a Hardcore Oxygenarian ascension
• painter's palette -- complete the PretentiousArtist quest
• palm frond -- visit with the PalmistParaphernalia
• skull and crossbones -- visit with the SwashbucklingGetup
• Crimbo present -- visit with the CrimboDuds
• radio tower -- visit with the RadioFreeRegalia
• recycling symbol -- visit with the Glad Bag GladRags
• star -- visit with the StarGarb
• pixel sword -- visit with the EightBitFinery
• 42 -- visit with the TerryclothTackle
• Crimbo pineapple -- visit with the TropicalCrimboDuds
• Crimbo wreath -- visit with the ArborealRaiment

There are also three special tattoos which have been given by Jick to players who have actually gotten real life KoL tattoos. zetareticula has a zombie bunny (see this forum thread for details), Daisy Cutter has a spooky hockey mask, scalpel, and pretty flower (see this thread for more), and corneliusv has a daisy (see this thread for the full discussion). However, apparently KoL tattoos are becoming common enough that Jick will no longer award anything special for them.