Top the previous poster's over-the-top insult.

Dude, when you die, they are only going to accept you in Hell under protest. The demons will have to construct a new wing of the complex to torture you in because Satan won’t want to smell your noxious flesh burning or listen to your wimpy screams.

You, sirrah, are an abecedary of tepid triviality: a abolete barbarian of choleric distemper, an egoistical fartleberry of gangrenous hamartomania, an inane jackanapes of knavery and lethiferous maledictions, a nascently oblique poetaster of quisquilian rhymelets, a scarebabe without teeth, an ugglesome villain of woefully xenophobic yearnings. In a word, sir, you are zilch.

[But it’s always great to hear from you, Skald!]

You’re a three-decker sauerkraut and toadstool sandwich with arsenic sauce!

You’re a jerk. A total knee-biter.

-Wait, haven’t I done you before?

You ain’t got enough scrunch in your craw to may a dadpatch!

You are a shockingly detestable misdemeanant and a reprehensible cantankerously-caterwauling derelict whose birth certificate is an apology from the condom factory.

You might possibly achieve an iota of dignity if you would only wear larger clothes to hide that brazen
spam-fed ass.

It boggles the imagination. Out of countless possible combinations of electrons, protons and neutrons, strung along nearly endless variants of DNA in the formation of cells, samples of which include Einstein, Shakespeare and Jesus, here you are. What an immense cosmic letdown.

Who cut your hair?

You are so mercifully free of the ravages of intelligence.

You seem like the sort of person that someone else might like.

BTW, who are you, exactly?

You are Trump.

He is one of those people who would be drastically improved by death.

Death’s too good for them.

Shakespeare is always good for a good tongue-lashing:

“That trunk of humours, that bolting-hutch of beastliness, that swollen parcel of dropsies, that huge bombard of sack, that stuffed cloak-bag of guts, that roasted Manningtree ox with pudding in his belly, that reverend vice, that grey Iniquity, that father ruffian, that vanity in years.”

“A most notable coward, an infinite and endless liar, an hourly promise breaker, the owner of no one good quality.”

Sod off, you pestilent spunk-trumpet, you malodorous fuck-muppet, you sodden apology for personhood, and all around waste of space.

Yo’ momma so ugly she look like you.

Yo momma so fat, it takes three minutes for her selfie to download.

When you show your best side, you look almost intelligent.