I would react realistically. Turn on the news, contact the local authorities, find the nearest bunker to shelter down in. Bring my laptop with a bunch of witcher games, some board games, including gwent, and just try hold out as long as I can until the witchers join our dimension to save us. :)

Read up on all of Andrzej Sapkowski's work to learn as much about the monsters as I can.

Get hit by a nuke.

Edit: Scratch that. I Would seek out MaxFulvus and stop him from offering virgins to them.

Get to a town or at worst small city because the bigger ones become magnets for chaos, anarchy and trouble.

Never played GWENT or The Witcher, but they're still on my backlog, but I think that hiding under a rock would be a great way of surviving

He would look for the elves to found Aretuza and I would teach him how to play Gwent <(￣︶￣)>

Since Clear Skies could protect against the Conjunction of Spheres I begin the search for Cursed Scroll in case of having the initiative. However, if the enemy was the first to attack, Land of a Thousand Fables may also be useful.

The above artifacts can alternatively be used to find Royal Decree, because, when confronting monsters, the help of Professional is often useful, and, in the case of a larger horde, Igni is sometimes irreplaceable.

I also equip Artefact Compression, because it can make a giant a liliput.

Prepared in this way, I leave my house and ask: Up for a round of Gwent?

So, let's get started) In the case of the beginning of the Conjugation of Spheres, I will perform the following actions in a strictly defined order:
1. I will gather my homies who shared with me the ambiguous "happiness" of playing the Witcher role-playing game.
2. Having discussed a plan for further actions, we definitely need a plan, we will get together and go on a (deadly) dangerous expedition to kill the main villain. Since because of the monsters our life has already gone to hell and we have nothing to lose, we, of course, will choose the most dangerous creature on Earth.
3. Since it is clear that not a single monster will cause such damage even in theory, like a nit sitting in the Kremlin, we will choose it as the target of the campaign (I repeat, so and so, we have nothing to lose).
4. Since hell is already happening everywhere, and there was already enough of it in the Kremlin, we can easily get to Moscow (Google maps show a two-month walk) and, I’m sure, I’ll find out that insane old man has already been eaten by some unknown garbage. Since this creature was smart enough to take Putler, we will first try to negotiate with it, so that later, when everything settles down, we will erect a monument to her. But if we fail, then we will have to run away from her collectively, and then try to take credit for killing the Beast (you know who I'm talking about).
5. Write a book about it, make a movie about it, make a game and get rich on this story when the Conjugation is completed and the Convention on the rights of nekkers is signed.
That’s all, STOPWAR

I'd be frantically browsing the web to find out what this Conjuction of Spheres is all about.

Well lil' ol' me wouldn't have a chance against a vamp or ghoul. As a result I'll just listen to Dan Vasc's version of 'toss a coin to your witcher' , gather together with my fellows, enjoy a Stout and hope for the best while preparing to defend ourselves.

*Holds up a Pint" To Humanity's good health!

If this happens, I'll nuke england and then fight the monster.

I would convince Elon Musk to create a virus that would connect over the network and access all the smartphones around the world. In the moment people looked at the smartphone screen, they would be captured and transformed into "reversible data" and then travel through the network until they arrive in a USB flash drive. With Ciri's help and in possession of the flash drive, we would go to another galaxy similar to Night City from Cyberpunk 2077, leaving the land and smartphones to monsters.

Obviously, call 911

https://youtu.be/UlFfz127OPs?t=9

I wouldn't do anything but watch the circus burn.

I would go and raid the nearest jewlery shop for all the silver in there and then make as much silver swords and or knives as i could at a forge(or whatever i can find taht is closest to a forge)