|Release date(s)||KOR 201105May 2011
NA 20110920September 20, 2011
JP December 13, 2012
Rusty Hearts is a free to play MMORPG video game developed by Stairway Games and published by Windysoft in Korea, Perfect World Entertainment in North America, Sega in Japan and Xunlei Games in China.
There are four basic playable characters with their respective avatars, which retains the same combat style but of different gender.
- Frantz Kruger, a vampire specializing in swords and battleaxes.
- Angela Strraugend, a witch specializing in magical swords and scythes.
- Tude MacLoud, a werewolf specializing in gauntlets and claw weapons.
- Natasha Borzenkova, a gunslinger specializing in revolvers and muskets.
Avatar skins which replace the main default characters' appearance and sound can be purchased in the in-game cash shop. Once purchased, the new character is created from level 1. Each avatar character has small changes to differentiate from their original such as slightly different animations or the speed of their moves, but for all intents and purposes, they share the same weaponry and special moves. The cost of creating any avatar character is for free.
- Roselle Vergerius, a mysterious traveller who shuns the daylight. The elder sister of Leila, she is implied to possess vampiric blood.
- She is a character utilizing the same weapons system and skill sets as Frantz.
- Meilin Chen, a female kung-fu master. Her nomadic and lone-wolf tendencies have led her to Bramunez to right the wrongs and bring peace.
- She is a character utilizing the same weapons system and skill sets as Tude.
- Edgar Grosvenor, a young boy with the soul of a grown man. Edgar roams the land of Bramunez seeking a cure for his affliction.
- He is a character utilizing the same weapons system and skill sets as Angela.
- Leila Vergerius, a young girl dressed in gothic lolita clothing who is the younger sister of Roselle.
- She is a character utilizing the same weapons system and skill sets as Frantz.
- Ian Jablonsky, Nadia's childhood friend and her secret agent.
- He is a character utilizing the same weapons system and skill sets as Natasha.
Long ago, the Bartbarod kingdom thrived near what is known today as Macedonia. The Royal family maintained a pure bloodline until a genetic mutation nearly wiped them out and gave rise to a new race of mutants called vampires. They in turn gave rise to new race of half-breeds, causing the pure-blooded vampires to grow wary. The ruler of the Vampires at this time, Lord Vlad, decided that he would eliminate the impurities that threatened the existence of his people and declared war against humans and half-breeds alike.
After the Black Plague had swept through Europe in 14th century, the great witch Philistia assembled the Hermetic Association of the Golden Seal, a unification of small rebel groups to fight against Lord Vlad's vampire army.
One of the nations affected by the plague was Rumania. Seeking protection from the plague, the country's royal family sealed themselves within Curtis Castle, but to no avail. Every member of the royal family succumbed to the sickness. The Hermetic Association of the Golden Seal, has tracked their target, the ancient vampire Lord Vlad, to Curtis Castle in Bramunez. Acting quickly, the Golden Seal team placed a powerful barrier upon the castle, sealing Vlad and his minions within. Now they plan their assault on Curtis Castle, to defeat Vlad once and for all.
Just as the operation begins, a group of strangers have arrived in the city of Bramunez. Calling themselves "Specialists", they possesess strange and powerful abilities that the Golden Seal team would be foolish to ignore. The strangers are encouraged to join the siege on the castle, but their goals and their pasts remain mysteries; even to each other.
These are characters which the players may play, and advance their classes and develop their skills accordingly.
- Frantz Kruger is a hybrid human-vampire and holds a strong grudge against Lord Vlad. His fiancée, Amelia ,turned into a vampire by Frantz in the process of trying to save her life after a fatal accident. Soon thereafter, Amelia disappeared and Frantz has made it his mission to find out what happened to his beloved fiancee. Teaming up with the Golden Seal Team, he catches a glimpse of a woman who appears to be Amelia, inside Curtis Castle.
- Angela comes from a small village in the Fog Forest of Rumania. She is a young witch apprentice sent to Bramunez in order to help in the siege on the Curtis Castle. Because she hasn't seen much of world outside her village before now, she can be a bit naive, even though she is quite tough.
- A lifelong wanderer, Tude MacLoud was attacked by a wolf in his travels. He managed to fend the beast off but not after it broke off one of its huge teeth inside his chest. Before long, Tude discovered that the wolf's bite and its tooth were having an effect on his body. His arm turned into a wicked claw that he keeps hidden within a bulky gauntlet. He was traveling from town to town to avoid arousing suspicion when he stumbled into Bramunez on a whim. In a serious case of wrong place at the wrong time, Tude was sealed within Curtis Castle when the Golden Seal team erected the barriers to trap Vlad inside.
- Natasha is a con-artist who travels from town to town with her sister, staging fake attacks from monsters and then swooping in to save the day. However, her stand at Castle Curtis is no con. The inhabitants killed her brother in cold blood, and she will not stop until vengeance is dealt.
- Voiced by: Chiaki Takahashi (Japanese) 
- Roselle arrived in Braumunez alongside her sister Leila Vergerius. Roselle, the elder Vergarius sister, is quiet, but very protective of her younger sister, Leila. She has a vicious fighting style that she's not afraid to use to defend her sibling. The sisters shun the daylight and are thought to possess Vampiric blood, but the source of this is a secret known only to them.
- No one knows exactly what brought this mysterious young lady all the way to Bramunez, nor do they dare ask her about the power that resides in her left arm. She's shy around the townsfolk but once she gets into Curtis Castle her fists and feet speak volumes. Her lightning fast techniques and the power of her mystic arm will ensure that Vlad's minions learn to fear the name Meilin.
- Voiced by: Ai Nonaka (Japanese) 
- Edgar is older and more skilled than he looks. After fusing with the demon blade, Crudelitas, he was cursed with the body of a child. Although he is a bit clumsy in his new body, his magical ability makes him a serious threat to Vlad's hordes. His reasons for enlisting are unknown, but his powers are so similar to Angela's that he may have crossed paths with her master, Rebecca.
- Voiced by: Kanae Itō (Japanese)
- Leila Vergerius, the young sibling of Roselle Vergerius, has been fighting to get out of the shadow of her protective sister. She hardly needs protection as she exhibits the same supernatural strength and affinity for dark magic as her sister Roselle. Leila is a gregarious and polite young lady whom the townsfolk have welcomed with open arms. If it wasn’t for her aversion to sunlight and her ability to go head to head with Vlad’s forces, she would fit right in with the older children of Bramunez.
- Voiced by: Norio Wakamoto (Japanese)
- Nadia's childhood friend and her secret agent. He survived the attack of monsters which killed all his other family members. He lived with Nadia's family when a noble visited Golden Seal Team adopted him, but his step parents were also killed by monsters. He organised mercenaries into a resistance to fight against monsters using his inherited wealth, but the organisation was disbanded due to betrayal of a member and now he works for Golden Seal Team to discover spies.
These are the more notable non-playable characters that the players may encounter in their gameplay.
- Voiced by: Masumi Asano (Japanese )
- Nadia is a Major from the Golden Seal Team. She gives the players quests that take them into Castle Curtis. For a fee, she can help the player form a guild.
- Voiced by: Ryōtarō Okiayu (Japanese)
- Vincent is a sergeant in the Golden Seal Team and also Nadia's younger brother. He seems to be able to go in and out of Curtis Castle unscathed and is otherwise very scholarly, intuitive and well-read.
- Voiced by: Hiromu Miyazaki (Japanese) 
- Gerald is the son of the Duke and head of the Golden Knights. He works hard in order to live up to the expectations of his father.
William Heo (Judah)
- Voiced by: Unshō Ishizuka (Japanese) 
- When his wife passed away and thus fallen into despair, Judah received a heart of metal from Vlad. When he has obtained the new heart, many people throughout Europe perished by the virus unleashed according to Vlad’s plan. Desiring his wife back, he worked secretly towards his goal.
- Voiced by: Akemi Kanda (Japanese)
- Melanie is the Countess of Curtis Castle. She appears to be a young girl between 6–10 years old, although her mannerisms and speech imply she may be more mature than her appearance lets on. She is the "owner" of Fluffy and the creature listens to Melanie's orders.
- Voiced by: Yuka Komatsu (Japanese)
- Amelia is Frantz's fiancée and a known Vampire. Her current whereabouts are unknown, although a woman who may or may not be Amelia was spotted by the Golden Seal Team inside Curtis Castle after Lord Vlad's siege on the town of Bramunez.
- Voiced by: Nobutoshi Canna (Japanese)
- An entity entrusted with the task of protecting the Lord of Vampires, Vlad. Unlike the lower-ranked Undead, it cannot be killed in a direct manner.
The closed BETA started on the 27 July 2011, however the high number users attempting to access the game caused long load times, and as a result many users were unable to take part in the closed BETA until the 28th of July 2011. Perfect World Entertainment announced at the launch that all Beta accounts would have their data erased prior to the release of the full game.
Phase 1 of the closed Beta ended on 17 August 2011 so that a large number of in-game changes could be implemented. Character Data was not erased in the transfer to the second closed Beta test, which began on 24 August 2011. Players who joined within the first 12 hours of the launch were given a special costume item for one character as part of the progression to open Beta.
There were initially three characters in the game (Frantz Kruger,Angela Strraugend and Tude MacLoud). These characters participate in the game's storyline. Natasha Borzenkova was added after the game was released from beta. Both Leila and Edgar were later made free and can be created via the character selection screen when the Rusty Hearts Reborn expansion pack was released.
There are characters which are free-to-play and some which are pay-to-create. For instance, unlike the first three premium characters, Leila Vergerius is initially free to play, but to obtain her, the player's account must be connected to Facebook. After the update patch on 31 January 2013, Meilin Chen, Roselle Vergerius, Edgar Grosvenor and Leila Vergerius are now free on the North American server.
- "「RUSTY HEARTS」正式サービスを明日（12月13日）開始。銃器による遠隔攻撃を得意とするキャラクター「ナターシャ」のプレイムービーが公開に" (in Japanese). 4Gamer.net.
- "「RUSTY HEARTS」のオープニングテーマをロックバンド・BREAKERZが担当" (in Japanese). 4Gamer.net.