Well, this sure is interesting, if nothing else.
Crypt things are medium-sized undead with unimpressive stats (+6 dex, +4 wis, +2 cha) and 6 RHD. They have a little bit of natural armor and some weak claw attacks. They also get Deflect Arrows as a bonus feat for some reason.
Crypt things have +4 turn resistance, but it only seems to work when within 50 ft. of 'the location or object it guards'. In theory that'd keep you from benefitting from it in a typical adventure, in practice you can just guard a random bauble and put it in your pocket. Either way, turn resistance is too niche to matter much.
The final ability a crypt thing has, and the most hilarious by a wide margin, is Scatter Defilers. Every creature within 30 ft. of the Thing (but no more than it has hit dice) get teleported 10d10 times 10 feet in a random direction (anywhere from 100 to 1000 feet, for those keeping track). It seems like it can't shift people up or down, it's only 1/day, and it isn't all that great if your enemies aren't in a hostile dungeon, but there's hardly a more hilarious way for a DM to split the party.
Anyway, -0 LA: the teleportation shenanigans are fun but not useful.