I'm gonna tell you gore idea A
Danny, like all ghosts, needs to shed his outer layer semi regularly. The problem is that as a halfa, his outer layer is not soft flexible ecto that can slink off like water, his outer layer is hard, solid fleshy meat and bone and skin, his human body. So where other ghosts simply have their outer layer slide off easily, Danny has to break out of his, which means bursting out of his own spine like a demented skeleton dripping in thick black ink that seemed to sizzle and vanish when dripping off, leaving his human body to fall to the ground while (over the course of somewhere between hours and 3 days) a new one forms around him to contain him back in human look.
Other less graphic effects of this shedding are new sharper teeth growing in, tougher nails (claws) and either after the first time or after multiple times, unlocking a third eldritch form that seemingly gets new features at a whim
Oh and if you want to make it dpxdc? Tim just happens to encounter Danny either right before, during, or right after a shedding. For the last one that could be finding the body that looks like it got chest bursted, the horrific goo monster Danny, or both.
Constantine is worried.
Oh, it doesn't seem like it, but the man has been chainsmoking and taking swigs from his flask at an alarmingly fast pace, swearing and sweating as Dark tries to dismantle enough of the massive ancient ritual circle before the solstice that it fails to fulfill its purpose.
What purpose exactly?
There was apparently a place between universes, and it was ruled by a monster, a dark god. Constantine had said the name ge knew the being by with an aura of fear...
Pariah Dark.
...
Danny wasn't feeling great. His power pricked restlessly under his skin. He kept getting flashes of numbness and fever.
His chest hurt.
He was curled up in the Team Phantom safe house in his boxers, laying in front of the blessed coolness of the air conditioner he'd managed to rig up.
Half dozing, something far away tugs at him. He bats it away but it doesn't stop. Soft poking becomes invisible hooks in his fevered body, the crown he thought he'd thrown away flaring into visibility on his head.
Constantine is is cursing loudly, shouting orders. They couldn't break the summoning in time, John and Zatanna both desperately putting everything they had into the banishment trap.
The symbols covering the massive cavern are pulsing, calling the god king to their realm. Magic clashes with magic, lightning pulsing between them and temperature plummeting.
With a surge of disorienting wailing and a blinding flash of toxic green.
The group stares at the apparent sick teenager who reflexively creates a radius of icy spikes, glazed eyes glowing an unnatural green. They're protective instincts spike against their accumulated stress, staring at the ethereal fire crown that's flickering in and out of existence over the clearly sick teens head.
He wretches, blood and bile pouring from his lips as the sound of cracking bones and wet tearing comes from inside his body. Constantine and Zatanna resume casting, pressing layers of invisible containment around the soon to be corpse.
Something is moving the body, and it is a body now. The chest is rippling like jelly until...
A shriveled claw laced with sparks of green lightning rips through the unfortunate boy, clawing into the flesh for leverage spreading frost along the skin.
Another hand emerges, claws impaling into the corpses thigh, struggling to be birthed into the world. Some is wretching in the background as unnaturally long arms drag a skull like head through the chasm of the boys chest.
The gaping body, dripping with liquid shadows releases a wailing monster into world. Shields shatter and ears bleed, but the spellwork works.
The magic currents leave the attending heroes and antiheroes on the floor, struggling to throw everything into the banishing spell. The creature thrashes, enraged, gouging the stone floor and shaking the cavern. With a great woosh of pressure, the creature is gone.
