Lethal
Fatal, mortal, life-threatening, destructive, harmful, detrimental, unhealthy, toxic, terminal, untreatable, deathly, mephitic, lethal, death-dealing, dangerous, injurious, pernicious, deleterious, noxious, poisonous, incurable, malignant, nocuous, and baneful.
Irreconcilable
Mortal, implacable, relentless, unappeasable, merciless, bitter, antagonistic, fierce, savage, irreconcilable, remorseless, unrelenting, unforgiving, pitiless, hostile, murderous, grim, and at each other's throats.
Impeccable
Unerring, impeccable, flawless, assured, true, accurate, exact, on target, inch-perfect, bang on, unfailing, perfect, faultless, sure, precise, correct, direct, on the mark, and spot on.
Absolutely
Completely, totally, perfectly, wholly, beyond, dead, in every way, in all respects, every inch, to the core, great, extreme, immoderate, absolutely, utterly, entirely, fully, quite, thoroughly, in every respect, one hundred per cent, to the hilt, intense, marked, excessive, and inordinate.
Boring
Boring, dull as ditchwater, uninteresting, uneventful, unstimulating, lacklustre, dry as dust, flat, monotonous, lacking variety, tedious, tiring, irksome, frustrating, soul-destroying, not up to much, samey, ornery, dull, dreary, unexciting, uninspiring, humdrum, dry, arid, bland, unrelieved, lacking variation, tiresome, wearisome, trying, mind-numbing, no great shakes, nothing to write home about, and dullsville.
Ashen
Deathly, ashen, white, wan, ghastly, deathlike, ghostly, pallid, and pale.