I read the translation by A.S. Kline, posted online at http://www.poetryintranslation.com/PITBR/Latin/Ibis.htm

An elegant expression of the darkest forces within humanity ... hatred & vengeance, war & violence, the inability to forgive ...

".................I’ll be your dearest enemy.
Moisture will sooner cease to conflict with fire,
the sun’s light be merged with that of the moon:
one part of the sky bring east and west winds too,
warm south winds blow out of the frozen pole:
spring with autumn, summer with winter, mix,
dawn and sunset lie in the same part of the sky:
new harmony rise with smoke, that an ancient
quarrel divides, from the brothers’ blazing pyre:
than you and I lay down, in a friendship that you shattered
by your crimes, these weapons we’ve assumed, cruel one."

"Your cortège is prepared: no delay to the sad prayers:
dread sacrifice, relinquish your throat to my knives.
Let earth deny its fruits to you, the rivers their waves,
let the winds and the breezes deny you their breath.
Let there be no heat to the sun, for you, no light for you
from the moon, let all the bright stars forsake your eyes.
Nor let fire or air offer themselves to you,
nor earth or ocean grant you a way.
Exiled, wander helpless, across the alien thresholds,
seek out scant nourishment with a trembling mouth.
Body never free of ills, mind of grievous sickness,
night be worse than day for you, and day than night.
May you be always pitiable, and yet let no one pity:
let men and women take delight in your adversity.
Let hatred for your tears be on you, be so fit to stink,
that when you might have known the worst of ills,
you’ll suffer more. And be, what’s rare, devoid
of common charity, a face offensive to your own fate."

"I’ll wage war on you: death will not end my anger, rather
among the shades it will set a cruel weapon in my hands.
Then, too, when I shall be dissolved in empty air,
my bloodless ghost will still revile all your ways,
then, too, my remembering shadow will pursue
remedy for your deeds, and my bony form your face.
Whether, as I’d not wish, I’m exhausted by long years,
whether I’m dissolved in death by my own hand:
whether I’m lost, shipwrecked by mighty waves,
while the foreign fishes feed on my entrails:
whether wandering birds pick at my limbs:
whether wolves stain their jaws with my blood:
whether any will deign to place me in the earth,
or give my corpse in vain to the common pyre:
wherever I may be, I’ll strive to break from Styx’s shores,
and, in vengeance, stretch an icy hand to where you are."