By reading documents written in various languages, Lara increases her understanding of that particular language, meaning she can read trickier murals and the like later in the game. If you haven't been following the pre-release (and post Xbone-release) press, you might be slightly confused about the notion of “leveling up language skills”. Crystal Dynamics have made a world that I want to scour, mostly to see all of the fine details and lovely artifacts rather than to harvest upgrades and experience points. I scoured the two major hub areas for hidden tombs and trinkets, and I leveled up Lara's language skills until I could read every scrap of parchment and monolithic signpost in the game. In fact, I've been enjoying it so much that I didn't do the sensible thing and rush through the plot so that I could write my review quickly. Over the next twenty hours or so, you'll guide her from branch-gathering and hide-hunting to full-on military engagements and supernatural shenanigans. As in the previous game, she's soon stranded in an unwelcoming environment with little in the way of equipment and no network of support. Lara Croft is still a young woman and we're witnessing the process by which she will become the titular crypt corrupter.
What it doesn't do is change the formula significantly. Rise of the Tomb Raider expands on and improves the core pillars of the series' 2013 reboot.