Probably Lucas Arts most original adventure game
There is a definitive tendency for people that describe games to use the term original quite a bit, it's handy, and, granted, if you haven't played a load of games, some would rightly merit the adjective linked to them. However, Day of the Tentacle was really wacky and crazy. For once, you will play as a squid... Don't sound too original? Well, that squid is the product of pollution and is looking to take over the world! That any more impressive to you?! Well, regardless of your take on crazy plot, you'll surely appreciate a game that while crazy with its puzzles, is never so crazy that you don't know what you have to be doing. Nope, this game's greatest achievement is that it managed to pack a lot of diverse puzzle experiences, without overloading you with loads of futile guesses, or with baking of your noodle that would just drive you to insane levels of frustration, as, unfortunately, many oldschool adventures would be in the business of doing. As such, Day of the Tentacle stands in a class of its own, with a uniquely told story, a fun packed load of puzzles, that at times might feel gratuitous and over the top, but well, it's a kind of adventure game high you're unlikely to find anywhere else. Maybe in Maniac Mansion, though, again, Day of the Tentacle is light years ahead of that on, in terms of story, puzzle design, visuals, animations and everything in between!