# Et tu, Brute? Then fall Caesar

This is a very difficult puzzle with a lot of references and ciphers.


This is the year 3019. At this point in time, we are technologically advanced. However, our population has declined. There are less than 2 billion people still alive on this earth. However, crime is still rampant. Many of the original third-world countries are now in anarchy. The European Union is disestablished. Russia has been conquered. No nation on the planet trusts each other. However, the United States has grown. Now the States has conquered all of the Americas. Yet, the country is still as democratic as it is today.

You are a Presidential Candidate from the newly founded state of Azyncia, located at modern day Argentina. Your opposition is John Trump from the District of Columbia and Siddharth Manglupati from the state of Texas.

The day before the presidential debate, you get an email from Manglupati. The message is as read:

HELP. ME. Fvyxi jsvgi ampp rsx wspzi xlmw sri jsv csy, Geiwev. I HAVE ENCRYPTED THIS SO THAT HE CANNOT SEE IT. KEY IS 1 LETTER.

Aoy srv iexliei cpgsv. Xevq vvty gdojg. Byl yfw avw nfv yil tygri. Gtxmbi, Wtilhv, Pfedlt. Ysmr zrmxfmvwm ml meyqiyr. Vhi snjaxk bbj vxig alrwe qcqm xze jxtkn. Tkuhh kxqguhg dqg irxu yhuvxv wzr kxqguhg dqg wzhqwb vhyhq. Txuq lw durxqg.

After the first part, you don't know what it means. The next day, the terrorist group, FOX, sends news that Manglupati is dead and that they have stolen national secrets and they plan to use it to pull off a nuclear bomb attack.

FOX is a group of elite terrorists who are so clever at hiding that no country has found any trace of their general location. The only clue that people have found is that their leader "is the man with no face." However, indigenous people as well as rebels in Africa have stated that FOX do not refer to themselves as "FOX" and that they are not located in Africa but they are trying to control it.

You continue in the election, but Trump has seized the electoral votes in the general poll. Even though you have a higher popular vote, because of the southern states having less electoral votes, you could lose in the final election.

However, the election is put on hold when the U.S. government issued an nationwide emergency.

As you head back to your bunker, the ground shakes under you. This was a nuclear attack of cosmic directions. Communications were knocked out on the other size of the planet. You run into your bunker immediately and close the seal. 5 days later, when you walk outside, you see or feel no nuclear residue. As you check your phone for a signal, you see that it is perfectly working. However, you check CNN news. A majority of the nuclear weapons were detonated on New York City, and among the losses was Presidential candidate John Trump.

You unanimously get elected President, and you vow to seek revenge on those who attacked the nation. However, you first need to answer some questions.

1. If the group "FOX" was not really "FOX", who were they?

2. Where are they based?

3. How did they manage to get hold of US nuclear weapons?

4. Why did they choose to bombard a single city to kill a candidate rather that spread the nukes across the nation?

5. Who killed Manglupati?

Hint 1

Solid Metal.

Hint 2

The Phantom Pain.

• I may answer some questions that you ask me, based on the question. – Azync Mar 23 '18 at 1:51

The first section of encrypted text:

Brute force will not solve this one for you, Caesar.
Is a vigenere cipher with the one letter key "e"

Using:

"Caesar" as the key to the second block of text

gets us:

you are getting close. very very close. but you are not yet there. otgkbe, etrjhr, xfnblp. gsvp znuxokvsu mu keuyihp. vdq swhats bkh vtqg jjrsm qlom the svtgv. ttshd sxzeudo dze infu hfurfv fxr gfqpshc lqp uzdywk thupq. cvum tw msrtyg.

Using:

"Et Tu Brute, then fall Caesar" as the key for the middle portion of text, we get: "Caesar, Caesar, Caesar. Your intellect is falling. The Answer has been there from the start."

Using a substitution Cipher:

We can make out "Three hundred and four versus two hundred and twenty seven. Turn i? around." Which seems to be a reference to the margin by which Trump won the US election (Took a bit of Googling for a Non-American there...)

Giving us the full message:

HELP. ME. Brute force will not solve this one for you, Caesar. I HAVE ENCRYPTED THIS SO THAT HE CANNOT SEE IT. KEY IS 1 LETTER.

You are getting close. very very close. but you are not yet there. Caesar, Caesar, Caesar. Your intellect is falling. The Answer has been there from the start. Three hundred and four versus two hundred and twenty seven. Turn it around.

It may also be worth noting:

From the Video Games tag, and Azync's previous puzzle, FOX is likely a reference to Foxhound from MGS, which ties in with the "Solid Metal" hint... I'm not awfully familiar with the games, but I do seem to recall XOF being a counter unit to FOX with a backwards logo? (Skullface may also be "The man with no face")

As such, I would guess:

The group is "Cipher" or "The Patriots" from the MGS series, as it was at one point led by Skullface, who sent troops to Africa, and used a parasite on his commander (A la Brutus) which destroyed their cognitative functions ("Caesar, your intellect is falling").

So (and I'm afraid I'm learning this as I go, due to no prior knowledge of the subject):

1) FOX is actually XOF or Cipher, led by Skullface
2) They are based in Camp Omega, Cuba a U.S Navel Base
3) They bribed ArmsTech into Developing REX missiles, which didn't show up on Radar?
4) I am struggling here, to the wiki seems to imply it is so they can blame another faction? Though if I'm honest, hitting a city seems overkill enough to kill one man, why would they WANT to destroy the country? Alternatively it was to kill Zero, Skullface's old boss?
5) Skullface

• You are doing pretty good! Keep going! – Azync Mar 23 '18 at 11:31
• I am just strugging on the ROT13(ghea vg nebhaq)... If it refers to the cipher text, I'm unsure how to further decrypt it, and if it points towards a key, I'm hard pressed to find it. Give me a while to think on it :p – Fifth_H0r5eman Mar 23 '18 at 11:40
• Correct me if I'm wrong, but I believe that I didn't include a ROT13? I think I included one ROT23 that can be derived from the phrase 3019. – Azync Mar 23 '18 at 11:50
• Oh no, you didn't. Rot13 tends to be used as you can't add spoiler tags to comments, so it stops people accidentally reading something they shouldn't. – Fifth_H0r5eman Mar 23 '18 at 11:53
• You are getting very close. I see you figured out that it was XOF, or Cipher, and that it was Skull face. Answer who killed Manglupati, Why did they nuke New York, their base location, and how they got ahold of nuclear weapons and I will mark it correct. – Azync Mar 23 '18 at 15:13

The first decryption by:

Caesar Cipher with key of s = o: "Brute force will not solve this one for you, Caesar"

Then a portion of the second:

"Xlv pos fbuifbf zmdps. Ubsn ssqv dalgd. Yvi vct xst kcs vfi qvdof. Dqujyf, Tqfies, Mcbaiq. Vpjo wojucjstj ji jbvnfvo. Sef pkgxuh yyg sufd xiotb nznj uwb guqhk. Qhree hundred and four versus two hundred and twenty seven. Qurn it around." Where h=e. Implying the need to apply another method of decryption using numbers and or reversed sequence (304 vs 227 a difference of 77 or 403 and 722 a difference of 319 and guessing that the capital letter Q is in some way important here as it substitutes for T in the "legible" portion.) Uncertain if the additional decryption is to be applied to this phrase or back to the original. Call that a question, is the next decryption based on the provided information to be performed on this "decryption" or on the original second encrypted text?

Trying to figure out further... :/

• I'm going to give you a sneaky hint – Azync Mar 23 '18 at 11:24
• You don't use the "turn it around" on a part of a cipher. – Azync Mar 23 '18 at 11:24