Yes of course you can, but make sure you add it to the comic issue they appeared in.
here is a list of characters
Lek-Var Maryam Cha-NaNah-UmEt-RogMister Tawky TawnyAphroditeErosHarmoniaEtta CandyAmoeba ManAngle ManBlue SnowmanClayfaceCrimson CentipedeEgg FuDoctor CyberDoctor PsychoEgg FuFireworks ManMouse ManPaper ManLoboBrimstoneManhuntersDiane MeadeTime TrapperGamblerHarlequinIcicleKiller CrocVandal SavageSirensHawkman(katar hol)HawkgirlBythBlackfireFadeaway ManI.Q.Matter MasterShadow ThiefSupergirlMechanical ManCave CarsonAbelCainDoctor DestinyKlarion the Witch BoyTeeklMan-BatThe Vampiric MonkWizardQueen of FablesHugo StrangeBlue DevilSwamp ThingTomcatRobin (Tim Drake)Robin (Damian Wayne)Robin (Jason Todd)Robin/Batgirl (Stephanie Brown)Batgirl (Bette Kane)Batgirl (Cassandra Cain)Robin (Carrie Kelly)Madame XanaduDoctor SpectroRainbow RaiderGerry ReganDesaadDoctor BedlamPied PiperDingbatsPower GirlCarapaxThinkerBonnie BaxterSugar and SpikeThe KeyGeneral ImmortusKid EternityShining Knightthe Viking PrinceOlympianCirceMad ModGreat TenAccomplished Perfect PhysicianAugust General in IronCelestial ArcherNinjaYetiDoctor OccultMentoSargon the SorcererThe VoidMonster MenMoon GangPsionsShadow DemonsAngel & the ApeBrother Power, the GeekFiddlerPaul GambiSuper-HipNocturnaJohn StewartKyle RaynerMa'alefa'akBoodikkaLairaMorroCyborg SupermanVentriloquist & ScarfaceFemale Furies*Artemiz
Well good luck on that, seems like a lot of work glad you are here to help.
Well until you learn please don't edit anything. Its very simple to learn just google how!!
What do you think?