This is old. There a couple of voat posts regarding this. I made one.

This was Cusack's message to Fox:

“I AM FOR A SATANIC DEATH CULT CENTER AT FOX NEWS HQ AND OUTSIDE THE OFFICES ORDICK ARMEYAND NEWT GINGRICH-and all the GOP WELFARE FREAKS,”

From this Vanity Fair piece :

Paul Leyden. Leyden, the writer of Cusack’s upcoming film The Factory, told a radio program that Cusack was “one of [his] favorite actors until [he] met him.” He continued, “Everyone thought he was a really nice guy (prior to filming) and all I can say is that it was a really nice day when he wrapped.”

and

His answer to the “living person you most despise” question? “Very tough question. They exist in the realm of war profiteers. These men and women are the lowest form of human consciousness, truly and completely spiritually fucked. Theirs is an amazing satanic dance : create a new market with war, bar competitors from the aftermath, then pay your own companies at a cost-plus basis, which guarantees profits, all at the taxpayers’ expense. They are the biggest welfare freaks on the planet.”

he blocked me early days

He's blocked me on twitter. I've never once interacted with him.

So I dug into this a bit further to find out why he was tweeting about Moloch (the tweet you've linked was a year ago). This was in relation to the Florida school shooting. He was pushing the idea that Trump, the NRA and the GOP are a death cult sacrificing kids via school shootings. Such as this one :

"I hope every one rembers right now - only issues that matter are defeating GOP death cult at ballots - & removing a treasonous - criminaly deranged serial sexual assaulting Nazi pimp nra blood whore from office before he can do more damage - everything else is just noise."

And this one where he links this 2012 NY Review of Books article claiming guns are Moloch, which in part reads:

"The gun is our Moloch. We sacrifice children to him daily—sometimes, as at Sandy Hook, by directly throwing them into the fire-hose of bullets from our protected private killing machines, sometimes by blighting our children’s lives by the death of a parent, a schoolmate, a teacher, a protector. Sometimes this is done by mass killings (eight this year), sometimes by private offerings to the god (thousands this year).

The gun is not a mere tool, a bit of technology, a political issue, a point of debate. It is an object of reverence. Devotion to it precludes interruption with the sacrifices it entails. Like most gods, it does what it will, and cannot be questioned. Its acolytes think it is capable only of good things. It guarantees life and safety and freedom. It even guarantees law. Law grows from it. Then how can law question it? Its power to do good is matched by its incapacity to do anything wrong. It cannot kill. Thwarting the god is what kills. If it seems to kill, that is only because the god’s bottomless appetite for death has not been adequately fed."

Here is what Twitter came up with for his tweets between 2/14/2018 and 2/20/2018. Weirdly, it doesn't list either the Moloch one, or the Mooloch tweet , but you can see him harping on the topic over multiple different tweets for several days.

Hannity called him out on it . Which led to a Twitter war between the two, though apparently Hannity removed his tweet.

TL;DR: Cusak is painting gun rights people as part of a child sacrifice cult. Alinsky, much?

Cusack is just confirming that children were sacrificed. Putting out information on it doesn't mean he's part of it.

These people are the devil itself and would sell out their own children if they won a prize from it.

Do not respond to these tweets! There have been a lot of these taunting attempts lately. I'm thinking they are trying to put names and faces on us and other researchers. Dont fall for it, remaining anonymous is our greatest weapon

One thing's for sure. .. if you look at his latest tweets, you can see Exactly what and Who he stands for!

Thought Moloch was an owl. That looks like a cowman.

I followed the Tweet stream back. The guy who posted the Moloch pic was replying to a previous tweet a year ago by Cusak . Interestingly, Jem also replied to that tweet (see last reply). Cusack tweeted: "Moolochs". It would be interesting to figure out what he tweeted right before this previous tweet.

https://twitter.com/johncusack/status/965381726087368705

Are you sure Cusack isn't just exposing this, rather than espousing?

It should be noted that all those cheering along the sacrifice ( in the JPG ) are Jews.

https://archive.fo/AzMxl :

John Cusack on Twitter: "Accurate - moloch… "

This has been an automated message.

Are you calling him a "One disgusting brazen motherfucking satanic pedophile."?

If so, is there reason other than this image that you have both shared?

I haven't heard of this guy in a while. Has there been speculation about him?

Does anyone know how he was connected to Hunter S. Thompson? The anything-goes writer (incentally, cough cough also a friend of John Kerry).

Severa people on the Twitter thread mention him.