Tiaru grew up on Romulus, always being watched by the Tal Shiar due to her father being classified as a traitor. Despite that, she went on to serve in the Imperial fleet and received her first command after she proved herself as an officer during the Dominion War.
- “Taris”: In 2409, Federation players meet Tiaru Jarok in the Hobus System, where she transfers the R.R.W. Lleiset's Intelligence Officer, Lt. Gaius Selan, to their ship to assist in uncovering the truth behind the destruction of Romulus. She later brings the Lleiset to the Iconia System to retrieve Gaius when the mission is complete.
- “Azure Nebula Rescue”: Tiaru Jarok provides the opening briefing to players and joins the battle in rescuing Romulan ships being held by the Tholian Assembly in the Azure Nebula.
- “Sphere of Influence”: Tiaru Jarok is part of the Romulan Republic's delegation sent to witness the activation of a recently-restored Iconian gateway. She later commands the Lleiset in combat against the Elachi at the Jouret System.
- “A Step Between Stars”: The Lleiset under Commander Jarok assists Federation and Klingon players in the Jenolan Dyson Sphere against the Undine. After the immediate threat is over, Commander Jarok wants to claim the Jenolan Sphere for the Romulan Republic, provoking a verbal confrontation between the three powers.
- “Republic Day”: The player visits the bridge of the Lleiset in orbit of New Romulus and meets with Tiaru Jarok and the rest of her crew.
- “Surface Tension”: Jarok is part of a Romulan Republic delegation attending a conference regarding ownership of the Jenolan Dyson sphere and the renewed Undine threat. She then commands the Lleiset in repelling a massive Undine invasion of the Sol and Qo'noS Systems.
- “Know Your Enemies”: Jarok comes to the player's aid when they are attacked by the Vaadwaur in the Nular System.
- “Capture the Flag”: The player aids Commander Jarok and her crew in retaking the Lleiset when the ship is boarded by the Vaadwaur in the Orlitus System.
- “Alliances”: Jarok is present at a meeting aboard the U.S.S. Voyager to discuss the formation of a coalition of Delta Quadrant species to counter the threat of the Vaadwaur.
- “What's Left Behind”: Jarok accompanies the player on a mission to investigate an Elachi subspace outpost. She then arrests Empress Sela when she is discovered onboard the station.
- “Blood of Ancients”: Jarok is seen attending a briefing on Earth Spacedock discussing the allies' plan to combat the Iconians. She is later seen at the Romulan Flotilla when the remaining forces regroup after the battle.
- “Broken Circle”: Jarok is present for the briefing prior to the Alliance's assault on the Herald Sphere.
- “Butterfly”: Commander Jarok, representing the Romulan Republic, gives support to an Alliance effort to use the K.I.S. Annorax to alter the timeline. By preventing the U.S.S. Yamato from ever re-discovering Iconia, the new timeline successfully delays the Iconian War and restores Romulus, but the planet has been assimilated by the Borg Collective. Jarok accompanies the player to the surface to recover data needed to correct the changes to the timeline.
- “Midnight”: Cmdr. Jarok attends the Iconian Resistance briefing aboard the Kyana Research Station in advance of the last battle of the Iconian War. She rejects any ethic quarrels about committing genocide against the Iconians by killing their last survivors ca. 200,000 years ago and demands to focus on the task at hand. She subsequently commands the Lleiset during the battle in Earth orbit.
- “The Temporal Front”: Jarok is present at the Alliance Summit on New Romulus.
- “Scylla and Charybdis”: Jarok and the Lleiset join Romulan Republic players in the defense of Bajor.
- “Storm Clouds Gather”: Commander Jarok accompanies Proconsul D'Tan to an Alliance summit on the Hur'q threat on Deep Space 9. Aboard the Lleiset she later aids in the defense of the station and nearby civilian ships.
- “The Centre Cannot Hold”: Jarok assists the player against Elachi forces emerging from a mycelial rift activated by House Mo'Kai forces in the Terrh System.
- “Trouble over Terrh”: Jarok assists the player in the Terrh System against Elachi forces.
- "Aftershocks": It is revealed that in the Mirror Universe, Commander Jarok is also in command of the I.R.W. Llieset; Admiral Leeta complains that she has been favored by the Emperor ever since her father allied with the Terran Empire. Leeta is ordered to surrender command of the I.S.S. Enterprise to Jarok, but she is able to escape with the ship.
- According to the developers, Tiaru Jarok is intended to be the female Romulan depicted on the Legacy of Romulus solicitation cover.
- Cmdr. Jarok keeps a replica of the Sword of the Raptor Star in her sleeping quarters aboard the Lleiset.