The Hitman video game series, developed by IO Interactive, allows its players to don the guise of a ruthless assassin and perform a variety of different jobs. It follows Agent 47, an elusive man whose questionable work leads him to confront his long-forgotten past.

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Each mission in the Hitman series permits a great deal of experimentation regarding how targets are disposed of. Some of these challenges can be bested quickly by simply locating the target, killing them, and sprinting to the nearest exit, while others require a more tactical approach. The latter is often an enjoyable and rewarding experience, but it can become tedious depending on the mission's layout and objective.

5 Situs Inversus - Hitman

Agent 47 concealing a gun behind his back in Hitman

"Situs Inversus" is the final mission of Hitman, and is thus one of the most challenging. Agent 47 begins the mission in the Gama private hospital, a secret facility that provides medical assistance to the "global elite." It operates outside the law and is, therefore, an exceptionally dangerous location to infiltrate. 47 must eliminate two targets during his time at Gama, but doing so is much easier said than done. Yuki Yamazaki is the most accessible target, but killing her without compromising 47's identity is a challenging feat to accomplish.

If the hospital's staff of visitors become aware of 47's presence, the facility will be placed under lockdown, rendering the assassination of both targets exceedingly difficult. Once Yuki has been quietly disposed of, Erich Soders will be the only person standing in 47's way. He is arguably the most difficult target to gain access to in the entire game due to the labyrinthian layout of the hospital. Once found, he can quickly be dispatched with one bullet, but it is recommended he be disposed of subtly to not alert security. "Situs Inversus" requires the player to be patient, making it one of the most frustrating Hitman levels to exist.

4 Holiday Hoarders - Hitman

Agent 47 in a Santa Costume in Hitman

The "Holiday Hoarders" mission in Hitman poses one of the greatest challenges in the entire series. It takes place in the same world allocated to "The Showstopper" but with a much more festive theme being implemented. Unlike his previous jobs, this unique spin on the life of an assassin requires 47 to find and dispatch two bandits before they steal a selection of Christmas presents. Failing to do so will result in a reduced score during the mission's climax, so the player should aim to prevent their thefts as soon as possible.

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Theoretically, this seems far less challenging than most of the game's content, but the confusing layout of the mansion makes it difficult to locate the thieves, who have both been named humorously after Harry and Marv from Home Alone. One of the challenges associated with this level requires 47 to dress as Santa Claus and collect all the presents before his enemies can, a feat that is not easily accomplished unless the pattern of the thieves' journey and the whereabouts of the presents are known. It is a deceptively tedious mission, but the festive atmosphere slightly diminishes its monotony.

3 Chasing A Ghost - Hitman

Agent 47 soaking in Mumbai's atmosphere in Hitman

The "Chasing a Ghost" mission in Hitman is one of the most laborious levels in the series. Lucas Gray has killed a member of Providence so Agent 47 is sent to Mumbai to deliver a deadly message in retaliation. Upon his arrival, he is tasked with assassinating three separate individuals related to the attack on Providence. Two of these targets can be disposed of with relative ease, but the location and appearance of Wazir Kale are unknown. To complete the level, 47 will have to do some digging, but the locations where he should begin his investigation are never explicitly stated.

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The streets of Mumbai are crowded with civilians and crawling with armed guards whose sole goal is to protect the targets. The level itself is quite expansive, so 47 will have to travel great distances to reach his enemies, but gaining access to them is never easy. Though most targets can be disposed of in a comical fashion, particularly Dawood Rangan, the requirements needed to do so bring the level's pacing to multiple halts. Completing "Chasing a Ghost" requires a tactical approach, but the length of the mission renders the experience a mundane one.

2 Nightcall - Hitman 2

Agent 47 approaching the Shadow Client's Home in Hitman

The "Nightcall" mission of Hitman 2 documents Agent 47's first appearance since the climax of Hitman. 47 arrives at Hawke's Bay via boat to infiltrate the home of the mysterious Shadow Client and uncover some intel in the process. Diana Burnwood hopes that, by doing so, she will uncover information on Agent 47's past, but the investigation quickly morphs into a bloodbath upon entering the house.

"Nightcall" is an engaging mission, but the choice to place it at the beginning of the game is questionable. Upon reaching the Shadow Client's presumed home, 47 will have to scavenge the exterior to find a way in. Most fans of the franchise were excited to jump back into the iconic combat and action Hitman is known for only to find the franchise's most enjoyable features confined behind puzzles. It is an enjoyable mission once these puzzles are completed, but having to do so during each playthrough is tiresome.

1 The Ark Society - Hitman 2

The Ark Society Headquarters in Hitman

The "The Ark Society" mission in Hitman 2 is one of the most overly convoluted missions present in the series. In the hope of capturing the Constant, a corrupt man with baffling power, Agent 47 travels to the Isle of Sgàil. Most of his missions up until this one have tasked him with executing his targets, so kidnapping is not a skill he is familiar with.

The Ark Society is chock-full of powerful and wealthy individuals, so it was already assumed the island would be covered in armed forces. To make matters worse, the Constant has injected himself with a poison that will only take effect if his life is threatened. To ensure this poison isn't activated, 47 must assassinate Zoe and Sofia, two members of Providence who possess kill switches, without being detected. "The Ark Society" mission permits little room for error, making it one of the most frustrating missions present in Hitman.

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