It was a blowout to end all blowouts! The entire Kardashian clan hooked up at The Blind Dragon karaoke bar in West Hollywood Sunday night to celebrate Khloe's 33rd birthday. Khloe appeared to have her present in her hands -- in the form of a tall basketball player wearing a very dapper get-up -- seriously, Khlo looks SO happy when Tristan's in town!

While we're DYING to know 1) what Tristan got Khloe for her birthday (a ring???!!!), we're also DYING to know 2) who lip-synched to what songs inside the bar! Did Kanye rap to A$AP Rocky lyrics and A$AP recreate "High Lights"? Did Kylie sing a Tyga track? Maybe Kris did a karaoke standard like "Wind Beneath My Wings"?

Speaking of Kris, she invited pal Melanie Griffith, while Kourtney came with Kim's personal assistant Steph Shep. Kanye arrived solo -- and Kim entered separately, through the underground parking garage, as did brother Rob. Yes, Rob Kardashian left his Calabasas couch for this!

Kylie arrived with BFF Jordyn Woods and Kendall showed up with a pal, but not after dining at Craig's with A$AP just before. Rocky arrived separately, but those two were TOTALLY together.

Looks like a fun party! Happy birthday, Khloe!