Some interesting facts about Higurashi's connetions to Umineko.

[Vivi]

Spoilers abound so be careful.

Spoiler:

Lambdadelta is the one who who gave Miyo Takano her wish of becoming a God.
From Lambda's diary:

Among boring humans like those, I met a little girl I thought to have a bit of knack.

"Tell me. What is your true wish? What is your predestination you say you'll definitely grant...?"
"I will become a god."
I granted her wish.
I gave her the guarantee that her endeavors would definitely come true. The determination she spoke of, to me, was already 'fate'.
And the guarantee I gave, to her too, was 'fate'.
That's why all the tales she will draw from now on will be fate.
Well, her fate also has a weak point.
Since her own endeavors are at the roots of it all, if they shake, so will her fate.

Spoiler:

Bernkastel and Lambdadelta had a game in the past.Which was the Hinamizawa Incident.
Lambdadelta Piece = Satoko and Miyo
Bernkastel Piece = Rika and Keiichi
Just how Beatrice and Battler were in a duel, the duel here was Keiichi vs Miyo.
Bernkastel mentioned that she was constantly trapped within a game.
This was due to Lambda being the witch of Certainty.

Also proven by how in Higurashi Rei Episode 4:
"I must return to being Furude Rika than the Witch Bernkastel"

As for the killer (Not revealing the name!)

Spoiler:

In Tsubasa it shows that Lambdadelta was the one who made the killer her piece just the same as Miyo.

This can also be proven by Lambdas name as it translates to Miyo.

And the most important fact perhaps:

Spoiler:

Miyo Takano is a close acquantance of Okonogi.
Okonogi is a man heavily involved with the companies of Rudolf and Hideyoshi (Husbands of Kyrie and Eva).
Miyo once teamed up with Okonogi in an attempt to break the Mirror on Rokkemjima.
This is highly important as:
Bernkastel once established a game where Rudolf,Kyrie and Battler were the killers and Hideyoshi is comfirmed to be involved in the murders somehow.However as it was just another game, the 3 are not the real killers however Hideyoshi is still involved in all somehow.

Interestingly, Okonogi is also the one who gave Ange her Bodyguard when she wanted to travel to Rokkemjima in 1998 and is hinted to know what happened in 1986, as he tells Ange that one cannot understand Evas behaviour towards her unless knowing what happened on the Island.

Spoiler:

Hanyu is also a witch involved in Umineko as from the 3rd game on she was indirectly involved, only taking action in 1998.Hanyu = Featherine who's memory device was broken.Can be see by Hanyus left horn having a crack

[sagemaster777]

But wait, isn't Hanyu basically a god?

[Vivi]

Originally Posted by sagemaster777

But wait, isn't Hanyu basically a god?

More a god created by Featherine working as her game piece though suffering from Amnesia.

The witches are insanely powerful.Creating a god is far from difficult to do especially when Featherine is horrendously broken.

Remember how Hinamizawa took place again and again?
Same happened on Rokkemjima 8 times except Featherine warped reality so hard that it only occured twice and the other 6 having been changed by her into being a part of her own Fantasy Novel despite them actually taking place.

[sagemaster777]

Ah, that actually does makes sense. Not to mention hanyu's name translates to "feather" and "in". It's interesting how things connect from both series.