These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 0.97 s (backtrack: 0/20).

[ebuild  N     ] media-libs/libdvdcss-1.4.3:1.2::gentoo  USE="-doc" 380 KiB
[ebuild  N     ] media-libs/libdvdread-6.1.3:0/8::gentoo  USE="css -static-libs" 387 KiB

Total: 2 packages (2 new), Size of downloads: 766 KiB