Ruon Tarka claims to have noble multiverse intentions in Star Trek: Discovery season 4 - but a string of red flags suggest he's surely lying. The entire galaxy faces destruction in Star Trek: Discovery's 32nd century. A dark matter anomaly (DMA for short) spanning five light-years has suddenly appeared, tearing through planets and colonies effortlessly. As Federation and non-Federation forces unite behind this common threat, Discovery's Paul Stamets has deduced the DMA is a man-made phenomenon with a machine at its center, controlled by some unknown force designated as "species 10-C," who dwell beyond the galactic barrier.
The Federation has voted to respond diplomatically. Discovery will venture toward the assumed location of species 10-c, and politely ask these rowdy neighbors if they'd mind switching off the DMA. Ruon Tarka (played by Shawn Doyle) has a different plan. The reckless Federation scientist wants to drop an isolytic bomb into the DMA, cutting off its power source, and with Cleveland Booker (David Ajala) joining his cause, Tarka has gone rogue. According to the backstory he gives Booker, Tarka was imprisoned by the Emerald Chain after the Burn and forced to conduct research. He discovered a totally peaceful parallel universe free from war, poverty and strife, but needs an immense amount of energy to travel there. Tarka claims to want the DMA's mysteriously massive power source for this purpose.
Running away to a peaceful universe doesn't sound like the Tarka we've glimpsed thus far in Star Trek: Discovery season 4. This is the Tarka who happily risked blowing up Discovery because "science." The same very Tarka who voted to tear chunks out of subspace rather than supporting his own employer's pleas for diplomacy. And it's Tarka's DMA plan that risks triggering a deadly war between his own galaxy and Unknown Species 10-C. These are not the actions of a man hoping for a quiet life in a tranquil, conflict-free universe - our first big red flag in Star Trek: Discovery season 4's "...But To Connect." Tarka's emotional manipulation of Cleveland Booker raises a second. Clearly still grieving after the DMA destroyed his home planet, Book isn't thinking rationally in Star Trek: Discovery, and Tarka has taken advantage of that sadness for his own ends. The promise of a peaceful world out in the multiverse is the perfect lie for a man devastated by Kwejian's destruction, meaning Tarka gets an eager, willing pilot for his spore drive.
Add to that Ruon Tarka's shady demeanor, supreme arrogance, and the very strong possibility of knowing more about the DMA than he's letting on, Tarka is surely either not telling Booker the full story, or lying outright. The scar on Tarka's neck at least proves he was an Emerald Chain captive, and the part about researching parallel universes tracks logically. But Tarka doesn't explain how he escaped the Emerald Chain when his close friend and partner didn't. Perhaps Tarka secretly made contact with entities from another universe without the Emerald Chain finding out. They agreed to to liberate him from Osyraa in exchange for Tarka opening a gate between universes. The true purpose of the scientist's DMA bomb may be to tear a rift between worlds, allowing Tarka's co-conspirators to invade.
Alternatively, Tarka might've been honest about migrating to a peaceful universe... but to dominate it, rather than live there happily. The DMA is dripping with energies from the galactic barrier. Though usually fatal to regular humans, the "strange energies" helped Star Trek: The Original Series' Gary Mitchell transform into a God-like being. Maybe Tarka believes he can successfully recreate that process on himself, then traverse universes to rule over somewhere with "no war, no Burn, no Emerald Chain." Ruon Tarka may then become a common enemy that brings the Federation and Unknown Species 10-C together in Star Trek: Discovery season 4.