Two of my favorite games handle the issue of language—what the heck it sounds like when the PCs and NPCs are talking—very differently. Today…Dungeons and Dragons!
More Barriers Than You Think: In 4th Edition D&D, there’s a lingua franca: a language called “Common.” But it’s not truly universal. In fact, it isn’t even particularly widespread. Sure, a lot of creatures—including all the PCs—speak Common. But many key creatures don’t, including entire categories like angels, archons, beholders, most demons, most devils, driders (curious given that they used to be Common-speaking drow, huh?), efreets, elementals, giants, lizardfolk, salamanders, slaads, treants, troglodytes, trolls…and those are just the heavy hitters.
Some of the above speak Supernal, of course, but Supernal doesn’t enable universal communication. If you speak Supernal, everyone understands you. You don’t necessarily understand their non-Supernal replies.
Why Do Languages At All? The conventional wisdom is that it’s sometimes fun to try to play through a language barrier, resorting to pantomime and gesture to communicate with a monster. And there’s a long D&D tradition of PCs collectively learning an obscure language and using it to talk among themselves when NPCs might overhear them.
I think the first part of that conventional wisdom is largely bogus; the pantomime encounter is fun once or twice, but it becomes tiresome after that. And you can still have the occasional pantomime encounter without hard-coding so many language barriers into the game. Make those language-barrier situations what they truly are: the exception, not the rule.
I’m more sympathetic to the second use of the language barrier: a PC-only language. It has a nice side effect: It provides a degree of story-legitimacy to the table-talk that happens among the PCs anyway. But again, the many language barriers seem to be forcing the issue a bit.
I guess there's a third reason for the existing system: The game designers' natural inclination to reward PCs who expended the effort to learn the languages in the first place. But in 4th edition, those language choices (if indeed your character gets any choices at all) are almost entirely made at character generation. And if you quiz the third floor at Wizards, I doubt you'll get many designers who say they want lots of players picking up the Linguist feat. That reason, though well-intentioned, is the most bogus of all. Rewarding someone for being an elf is the same as punishing someone for not being an elf.
It's All About Monster Dialogue: The real point where the rubber meets the road is with NPCs talking to other NPCs, however. The D&D language system has created a world where monsters can’t talk to other monsters--not as easily as I'd like, anyway. And in a game that stresses heterogenous monster mixes in a given encounter—and monsters with identifiable roles in combat—that’s a problem.
It’s better for the game if the leader monster can shout out to the skirmishers “Stop the one with the crystal!” or tell the artillery, “Cover me while I retreat to the Sanctum of Skulls!” As a DM, I usually want the PCs to overhear stuff like that. It adds some exposition, some verisimilitude, and a tactical hint—and it gives me a way to provide some color and characterization for the monsters. Even if the PCs don’t understand the language the monsters are using, they’ll get a different vibe from a harshly whispered “Ruthek kaura naaa…ruthek kaura naaa…” or a hysterical, screaming “Ruthek kaura naaa! Ruthek kaura naaa!”
But a lot of monsters can’t talk to each other. I once flipped through the Monster Manual and looked for language barriers in the sample encounters. I don’t remember the exact figure (and I’m not about to duplicate the effort), but somewhere in the neighborhood of 30 percent of the sample encounters include a language barrier. And that doesn’t count sample encounters where one of the monsters is a hyena or something that doesn’t speak at all. No one at the table is going to bat an eyelid at that. But the number of “intelligent speakers that can’t talk to the rest of the intelligent speakers the Monster Manual groups them with” is way too high.
And the language barriers strewn throughout the game can jump up and bite a DM when no one’s expecting it. All it takes is one curious player to say, “Hey, what language is the fire titan ordering the fire archon around in?” At the very least, that creates a needless “um…” moment for the DM.
Quit Throwing Bricks, Dude: So what should you do? Well, you can play it as it lies, of course. Embrace those language barriers. Show the fire titan gesturing wildly at the fire archon. Have the red dragon wing-slap the salamanders into position. There are too many language barriers for my table, but there might not be too many for your table. And that’s what really matters, huh?
Alternatively, you can make a really expansive interpretation of DMG 171: “intelligent creatures [the PCs] encounter speak at least a little Common.” You can decide for your table that “a little Common” is enough to engage in light conversation, give and receive tactical commands, taunt the PCs, beg for mercy, and deliver key clues. You’re pushing the envelope of that rule’s intent—heck, you’re probably outside the envelope. But I think the payoff at the table is pretty good. You don’t get stuck with monsters that can’t talk to each other. Their choice of language is the spice, not the stew. And that's the way I think it ought to be.
Out of Context: "It's an RP realm. You're supposed to say, 'Weep more, novice.'"