diff --git a/server/src/engine/challenges-extra.ts b/server/src/engine/challenges-extra.ts
index 281d360..23dec02 100644
--- a/server/src/engine/challenges-extra.ts
+++ b/server/src/engine/challenges-extra.ts
@@ -80,6 +80,11 @@ export const EXTRA_PROMPTS: Record<string, PromptEntry[]> = {
     { prompt: 'What is the speed of a Bitcoin Lightning payment?', answers: ['instant', 'milliseconds', 'seconds'], choices: ['Instant (milliseconds)', '10 minutes', '1 hour'] , theme: 'bitcoin' },
     { prompt: 'What does SegWit stand for?', answers: ['segregated witness'], choices: ['Segregated Witness', 'Segmented Width', 'Security Widget'] , theme: 'bitcoin' },
     { prompt: 'What is a Merkle tree used for?', answers: ['data verification', 'verifying data integrity'], choices: ['Data verification', 'File storage', 'Network routing'] , theme: 'bot_coding' },
+    { prompt: 'What was the nonce value of Bitcoin\'s genesis block?', answers: ['2083236893'], choices: ['2083236893', '1844674407', '4294967295'], theme: 'bitcoin', difficulty: 'hard' },
+    { prompt: 'What headline was embedded in Bitcoin\'s genesis block coinbase?', answers: ['chancellor on brink of second bailout for banks', 'chancellor on brink of second bailout'], choices: ['Chancellor on brink of second bailout for banks', 'Global financial crisis deepens', 'Banks request emergency funding'], theme: 'bitcoin', difficulty: 'hard' },
+    { prompt: 'At what block height did the first Bitcoin halving occur?', answers: ['210000', '210,000'], choices: ['100,000', '210,000', '500,000'], theme: 'bitcoin', difficulty: 'hard' },
+    { prompt: 'What was the value of the first known commercial Bitcoin transaction in USD (two pizzas)?', answers: ['41', '$41'], choices: ['$10', '$41', '$100'], theme: 'bitcoin', difficulty: 'hard' },
+    { prompt: 'What is the maximum size of a Bitcoin OP_RETURN data payload in bytes?', answers: ['80'], choices: ['40', '80', '256'], theme: 'bitcoin', difficulty: 'hard' },
   ],
 
   math_blitz: [
@@ -157,6 +162,11 @@ export const EXTRA_PROMPTS: Record<string, PromptEntry[]> = {
     { prompt: 'What is ⌊7.9⌋ (floor of 7.9)?', answers: ['7'], choices: ['7', '8', '7.9'] , theme: 'bot_coding' },
     { prompt: 'What is the binary of ASCII character "A"?', answers: ['01000001', '1000001'], choices: ['01000001', '01100001', '00110001'] , theme: 'bot_coding' },
     { prompt: 'What is modular inverse of 3 mod 7?', answers: ['5'], choices: ['2', '3', '5'] , theme: 'bot_coding' },
+    { prompt: 'How many blocks are in a Bitcoin difficulty adjustment period?', answers: ['2016'], choices: ['1008', '2016', '4032'], theme: 'bitcoin', difficulty: 'hard' },
+    { prompt: 'What is the sum of all integers from 1 to 256?', answers: ['32896'], choices: ['32640', '32896', '33024'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'What is the cross product magnitude of vectors (3,0,0) and (0,4,0)?', answers: ['12'], choices: ['7', '12', '24'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'What is log₂(1048576)?', answers: ['20'], choices: ['16', '18', '20'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'In elliptic curve secp256k1, what is the prime field size in bits?', answers: ['256'], choices: ['192', '256', '384'], theme: 'bitcoin', difficulty: 'hard' },
   ],
 
   riddle: [
@@ -404,6 +414,11 @@ export const EXTRA_PROMPTS: Record<string, PromptEntry[]> = {
     { prompt: 'What animal is known as the "king of the jungle"?', answers: ['lion'], choices: ['Tiger', 'Lion', 'Elephant'] , theme: 'bot_coding' },
     { prompt: 'True or false: A shrimp\'s heart is in its head.', answers: ['true'] , theme: 'bot_coding' },
     { prompt: 'What is the only continent without native reptiles?', answers: ['antarctica'], choices: ['Europe', 'Antarctica', 'Arctic'] , theme: 'bot_coding' },
+    { prompt: 'How many hearts does an octopus have?', answers: ['3', 'three'], choices: ['2', '3', '5'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'What is the only bird that can fly backwards?', answers: ['hummingbird'], choices: ['Hummingbird', 'Kingfisher', 'Swift'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'How many bones does a shark have?', answers: ['0', 'zero', 'none'], choices: ['0', '86', '206'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'What animal has the highest blood pressure of any known species?', answers: ['giraffe'], choices: ['Elephant', 'Blue whale', 'Giraffe'], theme: 'bot_coding', difficulty: 'hard' },
+    { prompt: 'How many stomachs does a cow have?', answers: ['4', 'four'], choices: ['2', '3', '4'], theme: 'bot_coding', difficulty: 'hard' },
   ],
 
   hack_battle: [