diff --git a/chals/crypto/hidden-runes/challenge.yml b/chals/crypto/hidden_runes/challenge.yml
similarity index 96%
rename from chals/crypto/hidden-runes/challenge.yml
rename to chals/crypto/hidden_runes/challenge.yml
index 514faeb..4d43091 100644
--- a/chals/crypto/hidden-runes/challenge.yml
+++ b/chals/crypto/hidden_runes/challenge.yml
@@ -1,4 +1,4 @@
-name: "Hidden Runes"
+name: "XOR 101"
 author: Sophia
 category: Crypto
 description: |-
diff --git a/chals/crypto/hidden_runes/flag.txt b/chals/crypto/hidden_runes/flag.txt
new file mode 100644
index 0000000..172a94c
--- /dev/null
+++ b/chals/crypto/hidden_runes/flag.txt
@@ -0,0 +1 @@
+sigpwny{alphabets_are_very_fun}
\ No newline at end of file
diff --git a/chals/crypto/hidden-runes/mysterious_message.txt b/chals/crypto/hidden_runes/mysterious_message.txt
similarity index 100%
rename from chals/crypto/hidden-runes/mysterious_message.txt
rename to chals/crypto/hidden_runes/mysterious_message.txt
diff --git a/chals/crypto/hidden-runes/solution.txt b/chals/crypto/hidden_runes/solution.txt
similarity index 100%
rename from chals/crypto/hidden-runes/solution.txt
rename to chals/crypto/hidden_runes/solution.txt
diff --git a/chals/crypto/password-cracking/challenge.yml b/chals/crypto/password_cracking/challenge.yml
similarity index 100%
rename from chals/crypto/password-cracking/challenge.yml
rename to chals/crypto/password_cracking/challenge.yml
diff --git a/chals/crypto/password_cracking/flag.txt b/chals/crypto/password_cracking/flag.txt
new file mode 100644
index 0000000..f36502f
--- /dev/null
+++ b/chals/crypto/password_cracking/flag.txt
@@ -0,0 +1 @@
+sigpwny{code_br3aker_!}
\ No newline at end of file
diff --git a/chals/crypto/password-cracking/hash.txt b/chals/crypto/password_cracking/hash.txt
similarity index 100%
rename from chals/crypto/password-cracking/hash.txt
rename to chals/crypto/password_cracking/hash.txt
diff --git a/chals/crypto/password-cracking/solution.sh b/chals/crypto/password_cracking/solution.sh
similarity index 100%
rename from chals/crypto/password-cracking/solution.sh
rename to chals/crypto/password_cracking/solution.sh
diff --git a/chals/crypto/password-cracking/wordlist.txt b/chals/crypto/password_cracking/wordlist.txt
similarity index 100%
rename from chals/crypto/password-cracking/wordlist.txt
rename to chals/crypto/password_cracking/wordlist.txt
diff --git a/chals/crypto/xor_101/chal.py b/chals/crypto/xor_101/chal.py
new file mode 100644
index 0000000..cc402cd
--- /dev/null
+++ b/chals/crypto/xor_101/chal.py
@@ -0,0 +1,14 @@
+def encrypt(message, key):
+    return bytes([b ^ key[i % len(key)] for i, b in enumerate(message)])
+
+def main():
+    passphrase = input("Enter passphrase: ")
+    key = [ord(char) for char in passphrase]
+    message = b"sigpwny{fake_flag}"
+    
+    # Encrypt
+    ciphertext = encrypt(message, key)
+    print("Encrypted message:", ciphertext.hex())
+
+if __name__ == '__main__':
+    main()
\ No newline at end of file
diff --git a/chals/crypto/xor_101/challenge.yml b/chals/crypto/xor_101/challenge.yml
new file mode 100644
index 0000000..2c16ad1
--- /dev/null
+++ b/chals/crypto/xor_101/challenge.yml
@@ -0,0 +1,26 @@
+name: "XOR 101"
+author: Sophia
+category: Crypto
+description: |-
+  Breaking news: Seals have reached a new level of intelligence and can now create their own XOR challenges.
+  One left a comment on a photo of themself. Can you use that to discover the flag?
+
+  **author**: Sophia
+value: 150
+type: dynamic
+tags:
+  - easy
+extra:
+  initial: 150
+  decay: 125
+  minimum: 100
+flags:
+  - sigpwny{seals_like_x0r}
+files:
+  - message.txt
+  - chal.py
+  - seal1.png
+hints:
+  - Can you use information from the seal photo to decrypt the message?
+  - Exiftool is helpful.
+state: hidden
diff --git a/chals/crypto/xor_101/flag.txt b/chals/crypto/xor_101/flag.txt
new file mode 100644
index 0000000..9dce13f
--- /dev/null
+++ b/chals/crypto/xor_101/flag.txt
@@ -0,0 +1 @@
+sigpwny{seals_like_x0r}
\ No newline at end of file
diff --git a/chals/crypto/xor_101/message.txt b/chals/crypto/xor_101/message.txt
new file mode 100644
index 0000000..b213103
--- /dev/null
+++ b/chals/crypto/xor_101/message.txt
@@ -0,0 +1 @@
+07060a110301100806030601001a13301e15151d1d160539052a11440612
\ No newline at end of file
diff --git a/chals/crypto/xor_101/seal1.png b/chals/crypto/xor_101/seal1.png
new file mode 100644
index 0000000..5b925eb
Binary files /dev/null and b/chals/crypto/xor_101/seal1.png differ
diff --git a/chals/crypto/xor_101/sol.py b/chals/crypto/xor_101/sol.py
new file mode 100644
index 0000000..e9642b6
--- /dev/null
+++ b/chals/crypto/xor_101/sol.py
@@ -0,0 +1,18 @@
+# Step 1: Inspect "comment" tag in metadata for passphrase (ex: exiftool seal1.png)
+passphrase = "tomatoisafruit"
+
+# Step 2:
+def decrypt(ciphertext, key):
+    return bytes([b ^ key[i % len(key)] for i, b in enumerate(ciphertext)])
+
+# Provided from message.txt
+input = "07060a110301100806030601001a13301e15151d1d160539052a11440612"
+
+# Convert hexadecimal string to bytes
+b_input = bytes.fromhex(input)
+
+# Use key to decrypt
+key = [ord(char) for char in passphrase]
+output = decrypt(b_input, key)
+
+print("Flag:", output.decode('utf-8'))