Resident Evil is the most famous survival horror game franchise of all time. Debuting with the 1996 release of the original game, there are now dozens of mainline installments and spin-offs. However, due to its status as a veteran franchise, it's also one of the hardest survival horror series to 100% complete. Later games like Resident Evil 7 have tons of content, and fully completing it all is a grueling task.

100% completion means two things here. For games with an achievement/trophy list, 100% completion will mean getting all of them, including DLC packs. For older entries without any achievements, 100% completion is more traditional: unlock and beat everything. Both mainline installments and spin-offs are fair play for the discussion, even comparatively forgotten games like Umbrella Chronicles and Darkside Chronicles.

10 Resident Evil 2 Classic Requires Repetition

Six A Ranks In A Row?

Not all the older Resident Evil games are harder than their remakes, but RE2 Classic gets the edge in of difficulty. Yes, there's no Ghost Survivors DLC, which ramps up the difficulty quite a bit in RE2 Remake, but the original has something worse. To unlock the Tofu Survivor in the original, you must beat the game six times in a row with an A rank. There are only four story campaigns, so you have to do two extra playthroughs just to unlock this mode.

The 4th Survivor and Tofu Survivor are much harder in the original, as bopping and weaving these zombies with tank controls introduces a considerable layer of additional difficulty. I've never been able to beat either, even with the infinite ammo cheat. 4th Survivor in the remake is still hard, but it's much more doable thanks to the third-person controls, and it feels much tighter.

9 Resident Evil – Code: Veronica X Allows No Mistakes

The Hardest Classic RE Game

Resident Evil - Code: Veronica turns 25 this year, and despite its age, it actually received an achievement/trophy list when the title got a remaster for PS3 and Xbox 360 back in 2011. This achievement list is brutal. While there are only 12 achievements, two in particular prove to be major problems.

A-ranking with Wesker takes some serious skill.

First up, there's the Weapon Crazy achievement for obtaining the infinite ammo Rocket Launcher from story mode. Code: Veronica is no doubt the hardest classic RE game to achieve an A rank in, requiring a perfect run with no saves or retries.

Thankfully, the unlimited herb glitch helps here, but it's still nerve-wracking playing those dangerous sections like the Nosferatu fight. Then there's the Battle Master achievement, which will require you to A-rank every character in Battle Game, including the knife-only Wesker. A-ranking with Wesker takes some serious skill and luck to pull the magnum from the Casino instead of the diary.

8 Resident Evil 1 Remake Overburdens The Player

Some Brutal Extra Game Modes

Resident Evil 1 Remake is already a challenging game, but 100% completion proves to be another story. You'll need to beat the game without saving and do a knife-only run, which is pretty difficult on its own, but it gets even harder. Real Survival mode is the ultimate test. The game defaults to Hard difficulty, there is no auto-aiming, and item boxes are not linked. This completely changes the game, and you'll have to mix up your routing. Invisible Enemy, on the other hand, isn't too hard, as one can play on Very Easy.

Surprisingly, the most annoying achievement is Every Nook and Cranny. This achievement forces you to pick up every item in every room in the game. In a survival horror title, where inventory is limited, this feels like a rough grind, going back and forth to the item boxes. Make sure to get the shotgun ammo in the lab prisoner room before heading to the helipad, as it's easy to miss.

7 Resident Evil 0 Presents Killer Tasks

A Nearly Two-Hour Extra Game Mode

While still not as hard as Code: Veronica, Resident Evil 0 is a step above RE1 Remake in of difficulty. The general game difficulty is more challenging, and beating the game on Hard mode feels like you're just getting by with the sparse tools the title gives you. Then, there are the immense tasks. One must beat the game without saving, get an S rank, and finish without using any healing items at all. These can all be done on separate playthroughs, but it's still rough, although the infinite ammo Rocket Launcher makes this significantly easier.

Leech Hunter is the extra game mode in RE0, tasking you with collecting up to 100 leeches around the training facility. There are tons of monsters to ruin your day, and not only do you need to collect all 100 leeches, but you also have to kill all the enemies and collect all of only one color. A full run takes nearly two hours, making Leech Hunter one of the longest and hardest extra game modes in RE history.

6 Resident Evil Outbreak: File 2 Has Brutal Bonus Scenarios

Wildly Hard Boss Rushes

The last older Resident Evil without an achievement/trophy list, Outbreak: File 2 is significantly harder than File 1. 100% completion by itself takes a wild amount of time, as you'll need to finish every scenario's completion list, beat them all with every character, and beat them on the highest difficulty. However, the real kicker that makes this game one of the hardest in the series is the array of bonus scenarios.

Elimination 1 through 3 consist of regular enemies, but Showdown 1 through 3 are the boss rushes. These are absurdly hard. I must have tried Showdown 1 for about two hours before giving up, and I don't tend to give up easily. Even after finding all the secret weapons, I could not beat the final boss of Outbreak: File 1. I can't even beat Showdown 1, but Showdown 3 forces you to go through all the bosses in both games, plus more.

5 Resident Evil Revelations Makes Raid Mode Tough

Raid Mode Is Pure Hell

Both Revelations 1 and 2 are pretty challenging, but the original takes the edge in of time commitment. The campaign itself isn't too bad, minus Infernal difficulty. Getting past enemies here proves to be a Herculean task, and you will have to evade most of them, as ammo is incredibly sparse in this mode. However, Raid mode is where most of your time will be spent.

You must clear all stages on all difficulties with an S rank, a time-consuming and difficult grind that's frankly not very fun. Even ammo can be a problem in this mode, and clearing the Ghost Ship takes a lot of skill. According to TrueAchievements, this game is the longest completion in the series, with an average time of 100 to 120 hours.

4 Resident Evil: Operation Raccoon City Can't Be Ignored

Brutal S Ranks

It might fly under the radar when it comes to discussions of difficulty, but one of the hardest Resident Evil games to 100% is Operation Raccoon City. The cooperative squad-based shooter has tons of multiplayer achievements, as expected, and will require some boosting sessions to finish them all. The big kicker of the entire achievement list has to be getting an S+ rank on all missions on either Veteran or Professional. Operation Raccoon City is already a challenging game in Normal mode, so this will be a rough time.

Some missions are best played cooperatively, while others are doable solo. Since Professional gives you a score boost at the end, some levels are best played on Pro. Using a guide is a must here because, without the right strategies, you might have a really hard time even pushing forward to new checkpoints. The positive to this game is that the DLC achievements are easy, and you won't need to S+ rank the Echo Six campaign missions.

3 Resident Evil 6 Requires Grinding

A Single-Player & Multiplayer Grind

Resident Evil 6 is one of those games that's more time-consuming than actually difficult. However, time is money to an achievement hunter, so it matters. You'll need to set up plenty of boosting sessions to get all the multiplayer achievements in this game, requiring 100 agent and creature kills. The single-player is equally grindy, requiring you to max out all the skills available.

There's a way to cheese it, but it'll still take over 135 retries of the same area just to get the skill points you need, which doesn't sound like any fun. The positive here is that Professional mode isn't too bad, as you can simply load up the last sub-chapter of a level on Pro, and beating it will count as completing the entire level. That's a great way to speed up the completion process.

2 Resident Evil 7: Biohazard's DLC Dials It Up

Tons Of DLC Pain

By itself, Resident Evil 7: Biohazard would be one of the hardest RE games out there. The brutal Madhouse difficulty feels like an entirely different game, and unlike Resident Evil 2 Remake, there's no $5 rocket launcher DLC to help you here. There are also some tough challenge-run achievements, like beating the game without opening the item box or using only three heals. What really makes the game a top-three hardest RE is the DLC packs.

The Resource Manager achievement states that you can only open the item box three times, but all of those are mandatory.

Most of the DLC content is incredibly difficult, whether it's completing Ethan Must Die, surviving Night Terror, S-ranking all stages in Jack's 55th Birthday, or becoming the King of Games by beating Survival+ mode in 21. That's not even counting the two story DLC packs, which must also be completed on their highest modes. In of a raw single-player challenge, RE7 has to be the hardest overall game in the series.

1 Resident Evil 4 Remake Takes The Cake With One Achievement

One Achievement Makes The Difference

Resident Evil 4 Remake just barely gets into the hardest RE titles to 100 percent, and it's due to a single achievement. On release, the game was at least a little challenging since, in order to unlock the Handcannon (needed for the Gun Fanatic achievement), you had to beat Professional difficulty without bonus weapons from a fresh save. However, with the Mercenaries update, you can unlock the Handcannon through that mode, and it's very easy. The Separate Ways DLC achievement, Ada the "S+"py, is the big issue.

Unlike the main campaign, you're forced to S+ rank the DLC on Professional, which means you must beat Separate Ways from a fresh save in under two and a half hours and with only ten saves. There's no easy way out here. You must be skilled at the game and master the parry mechanic. Make sure to unlock the Chicago Typewriter, as it makes the S+ run a little bit easier, at least during the second half. Without the achievement, this Resident Evil game would be a piece of cake.

Source: TrueAchievements