All runes are legit.
Some gameplay tips:
# Name Level Drop Rate Boss (Best Drop) Difficulty 1 El 11 50.0570% Countess Normal 2 Eld 11 35.7067% Countess Normal 3 Tir 13 25.2019% Countess Nightmare 4 Nef 13 17.3264% Countess Nightmare 5 Eth 15 18.1371% Countess Nightmare 6 Ith 15 12.3528% Countess Nightmare 7 Tal 17 15.2770% Countess Nightmare 8 Ral 19 10.3674% Countess Nightmare 9 Ort 21 10.8664% Countess Nightmare 10 Thul 23 7.3346% Countess Nightmare 11 Amn 25 6.7373% Countess Nightmare 12 Sol 27 4.5255% Countess Nightmare 13 Shael 29 3.5940% Countess Nightmare 14 Dol 31 2.4055% Countess Nightmare 15 Hel - 1.8576% Countess Nightmare 16 Io 35 1.2409% Countess Nightmare 17 Lum 37 0.9323% Countess Hell 18 Ko 39 0.6222% Countess Hell 19 Fal 41 0.4701% Countess Hell 20 Lem 43 0.3136% Countess Hell 21 Pul 45 0.2361% Countess Hell 22 Um 47 0.1574% Countess Hell 23 Mal 49 0.1352% Countess Hell 24 Ist 51 0.0901% Countess Hell 25 Gul 53 0.0011% Andariel Hell 26 Vex 55 0.0008% Andariel Hell 27 Ohm 57 0.0011% Andariel Hell 28 Lo 59 0.0004% Andariel Hell 29 Sur 61 0.0004% Duriel Hell 30 Ber 63 0.0002% Duriel Hell 31 Jah 65 0.0002% Mephisto Hell 32 Cham 67 0.0001% Mephisto Hell 33 Zod 69 0.00003% Baal Hell
So to farm runes, it's best to farm nightmare Countess for middle runes and Hell Countess for high runes.