Fortunately, the cooperative puzzle-platforming remains as entertaining as in Guardian of Light. The most significant alteration is that Lara's Egyptian companions have access to a magical staff. This has several functions; elevating platforms, opening certain doors, and closing otherworldly portals. The beam can also be bounced off mirrors, a gimmick which is sprinkled into many of the puzzles.
Generally, Temple of Osiris excels at encouraging players to work together. Lara's grappling hook makes a return, meaning there's plenty of assisting one another to traverse gaps, and a couple of dicey abseiling puzzles where you'll inevitably be tempted to drop your companion into the abyss for a laugh (also see, laying a mine and then detonating it when your partner runs over it). They're hardly the most challenging puzzles, although a couple involving moving around giant metal orbs which explode on a timer had my fiancée and I scratching our heads for a short while.
Interspersed between puzzles are combat sections and sequences where you're chased by a giant crocodile-god-thing which sports a rather dapper mane. These are both fun, if again a little simplistic. The combat in particular could have been evolved a little to encourage cooperation, rather than simply throwing more guns at the player. There are a couple of enemies, such as skeletons protected by shiny shields, that require a little teamwork to dispatch, but for the most part a "spray and pray" approach remains largely effective. Even boss fights are pretty easy, with only one providing any real challenge, and that was mainly due to being fiddly rather than tough. Speaking of fiddly, avoid using keyboard and mouse if you can. The isometric viewpoint and fast-paced platforming just don't go well together with binary keyboard controls.
So, Temple of Osiris isn't going to tax your brain or reflexes to any great degree, but it makes up for this in pace and invention. Tombs take ten to twenty minutes to complete if you're on form, and each one either introduces a new object to the puzzling or is defined by a very clear theme. The tomb of the torturer, for example, is all ominous red lighting and deadly spike traps which culminates in an enormous spike maze, while another tomb is crisscrossed with ancient pipes funnelling natural gas which, when ignited, cause pools of water throughout the complex to boil.
At a time when so many games drag on needlessly, a game that plays so quickly, that gets straight to the point and wastes none of your time, is always refreshing. That said, the £24 price tag being bounced around by some shops is astonishingly expensive for such a brief game. £15 on Steam is more sensible, though I think £10-12 would be ideal. I don't like talking about game prices, but I've seen some pretty daft pricings for both large and small games lately, and it's something that ought to be mentioned.
In the end, Temple of Osiris is an acceptable sequel to Guardian of Light. It brings players more of what made Lara Croft's first cooperative adventure such a breath of fresh air, but goes no further than that, and some of its attempts to expand the game's scope are misdirected, although fortunately they don't damage the game too badly. If you're looking for something to play with friends or family over Christmas, you could certainly do worse.