The best HL creatures are the things on the ceiling that grab with their tentacle

A troll with a fair point, though. Valve obviously has some serious problems with continuing the series and in fact the situation is even worse than Duke Nukem Forever's. DNF already had problems because the team's ambitions required regular reboots, Valve additionally has to conclude a story that they probably don't even really want to work on anymore.

It would be hilarious though if Valve has DNF-syndrome and they've already created Half-Life 3 several times in secret, only to reboot it because they felt the technology had become outdated, the gaming industry had changed, etc. The fact is the game has become so ridiculously hyped "Half-Life 3" has become a cultural icon in gaming itself, and because it's been so long since HL2 Valve knows they will probably never be able to meet expectations.