Two questions about mapping

First is how I make skybox be visible at walls (always I put texture "f_sky1" in walls it see like texture, not skybox)

And last is how, for example; when I pick up a key monsters go to a linedef teleport.

What source port are you using? If you are creating a map for doom.exe or doom2.exe (known as "vanilla" DooM) you won't be creating a "skybox", exactly. What you will do is create a sector, and assign the F_SKY1 flat as your ceiling. This will create an "outdoor" sector. If you want to go further, and have a completely outdoor sector, with no walls surrounding the player, you'll need to create a border sector around your outdoor sector, assign it the same floor height AND ceiling height as your outdoor sector. [You'll have to insert other blocking sectors, such as a low wall, inside the border sector. Otherwise you'll have an invisible blocking wall when the player reaches the border sector.]

If you are using a source port that supports skyboxes, you will need to take additional steps. For ZDooM and its derivative ports, you can get more information on the wiki.

To have monsters teleport upon picking up a key, again, what you'll need to do depends on what source port you're using. For vanilla DooM, simply have a linedef in front of your key, and create a sector with a floor that can be lowered or a ceiling/door that can be raised. Set up the linedef to lower the floor/raise the door when the player crosses. The monsters will need to be behind the lowering/rising sector, and when the sector "opens" the monsters will be free to move forward. Then, in the path of the monsters set up a teleporting linedef that sends the monsters to the sector of your choice. You'll need to tag that sector and insert a teleport destination thing.

If you're using a source port such as ZDooM, you can activate the sector directly from the key itself. Again, refer to the wiki.

And here is an example wad that illustrates both of the items for which you had requested help:

Sky_Tele.zip

On 6/29/2019 at 9:37 AM, rebelagainstschool said:

First is how I make skybox be visible at walls (always I put texture "f_sky1" in walls it see like texture, not skybox)

Don't put f_sky1 on walls, put it on ceilings. It will turn the ceiling and the upper sidedefs of the respective sector into a sky in-game. Works in all formats, by the way.

On 6/29/2019 at 9:37 AM, rebelagainstschool said:

And last is how, for example; when I pick up a key monsters go to a linedef teleport.

Simple teleport ambushes are all across the IWADs, open up a map that has one, and see how it's made.

Easiest option for a teleport ambush is to make sure the monsters are alerted (usually with a small gap in the wall connected to their closet, allowing them to hear the player's gunfire) and make sure their path to a teleport linedef is blocked by a barrier of some kind.

You can place trigger lines around the key so that the barrier is removed when the key is picked up, allowing the monster(s) to teleport in.

12 hours ago, Kapanyo said:

Easiest option for a teleport ambush is to make sure the monsters are alerted (usually with a small gap in the wall connected to their closet, allowing them to hear the player's gunfire) and make sure their path to a teleport linedef is blocked by a barrier of some kind.

You can place trigger lines around the key so that the barrier is removed when the key is picked up, allowing the monster(s) to teleport in. 

Yeah I meant like wad UACLABS, when you pick up red key card begin spawn crazily demons xd

Thanx :b

About skybox worked fine ;)

Here is a step-by-step teleport ambush tutorial. This was written for the Eureka editor but you can use the same method for any map editor.

https://eureka.readthedocs.io/en/latest/cookbook/traps/index.html#teleport-ambush