A quick kino der toten easter egg for bo1 in case someone needs it:
1.Open your mapname.gsc and find the funciton named init_zombie_mapname() and paste this line in the bottom of the function 2. Sroll down in the bottom of the file and paste this code: 3. Go in radiant, and make some trigger_use , as much as you want, can be more than 3. Then press N at each of them and give them key: targetname value:meteor_trig
Then compile, don't also forget to build your sound too, but that's not a part of what im gonna cover, this is only the main part that you need.