SIGNAL LOST is a Half-Life mod based on/inspired by the Half-Life Alpha/Beta and Half-Life Uplink (the demo).
It stands as one of the most impressive GoldSrc mods developed. games
I’ve played it a few times and, I believe, I finished one of the versions. It plays like Half-Life (unsurprisingly) and looks incredible.
Besides that, I don’t have much else to say for now. On the one hand, I haven’t found the time to play it and, on the other, I’ve been supposedly waiting for a new release. Still: play it.