Quiz yourself
Quizzes
Multiple choice & flashcards across 17 topic sets. Test your knowledge and track your score.
Enter →Interactive Learning
Hands-on tools that let you explore concepts by doing, not just answering.
Enter →Load Custom Quiz
Upload a YAML, JSON, or encrypted .bsq question file.
🔗 Load from GitHub
Paste a public GitHub repo URL. BrainStuffer will find all compatible question files inside it.
🔒 Encrypt a Quiz File
Upload a YAML or JSON file, encrypt it with a password, and download a .bsq file. Share the .bsq publicly — nobody can read it without your password.
Question Template & Creator
Download a YAML template you can fill in yourself or feed to an AI/LLM to generate quiz questions. Or build one visually with the Quiz Creator.
🎓 Interactive Learning
x86-64 Instruction Visualiser
Step through MOV, LEA, PUSH/POP, ADD/SUB, CMP/Jcc, CALL/RET, XOR, INC/DEC, and SHL/SHR — watch registers, memory, and flags animate in real time.
9 instructionsx86-64 Register Aliases
Enter any 64-bit value and click RAX, EAX, AX, AH, AL to see exactly which bits each alias covers — live hex, decimal, and binary readout across all 24 registers.
24 registersData Sizes: BYTE · WORD · DWORD · QWORD
Click any size to see which bytes it covers in a 64-bit register, the little-endian memory layout address-by-address, and why 32-bit writes uniquely zero the upper half of RAX.
x86-64little-endianBit-Shift Byte Extraction
Enter any 64-bit value, pick a target byte (B0–B7), and step through the shr / shl / shr sequence that isolates it. Each shift animated with zeros flowing in.
Bitwise Flag Operations
AND to test a bit, OR to set it, XOR to flip it, NOT to invert. Step through 14 animated examples using a real Minesweeper cell byte — masking, toggling, packing booleans. Live interactive playground.
AND / OR / XORbit opsBit Flip
Transform a byte from start to target using bitwise ops — NOT, SHL, SHR, XOR, AND, OR. Solve each puzzle in par moves for 3 stars.
Puzzles • 10 levelsGate Gauntlet
A logic gate appears with a fixed input and a target output. Flip bits on Input B using number keys to make the output match the target. 30 levels — 4-bit to 8-bit, AND through XNOR.
Bitwise • 30 levelsRegister Race
Rapid-fire syscall and register trivia. Answer before the timer drains — build combos, survive 3 lives, beat your high score.
Speed • High ScoreAssembly Unscramble
Shuffled assembly lines — race against the clock to restore the correct order. 12 puzzles from basic syscalls to shellcode.
Speed • 12 puzzlesFakeStack
Step through a live x86-64 stack. Registers, frames, recursion, and overflow — chapter by chapter.
9 chaptersThe Stack
Push, pop, call frames, recursion, and stack overflows — visualised step by step with animated memory cells and interactive demos.
6 sectionsBinary Workbench
Live converter for binary, hex, decimal, and two’s complement with bit-level visualisation.
Number SystemsStack Sprint
Predict RSP and stack values after each instruction. push, pop, call, ret, sub rsp — watch the stack animate and test your mental model under the clock.
Interactive • 30 roundsLinux File Descriptors
Every I/O resource as a number. Explore stdin, stdout, stderr, pipes, sockets, TTYs and more — each colour-coded with interactive operations and redirection visualisations.
6 sectionsFD Table Simulator
Call open(), dup2(), pipe(), and close() via buttons and watch the file descriptor table update live.
Memory Layout Builder
Drag segments — .text, .bss, heap, stack, vDSO — into correct positions on a virtual address space diagram.
Memory Attacks
Step through buffer overflows, heap corruptions, use-after-free, TOCTOU races, and data races — each with animated memory visualisations.
6 sectionsFormat String Playground
Simulate printf(user_input) against a live stack. Watch %p/%x leak values and see %n become a write primitive.
RE Methodology
Walk through a real RE workflow: strings → ltrace → disassembler → xrefs → binary patching. Analyse a crackme from scratch with quiz questions at each step.
Stack Frames Visualized
Step through 9 instructions as DrawSquare calls DrawLine. Watch EBP and ESP change against a live memory diagram — push ebp, mov ebp,esp, sub esp,8, leave, ret all explained.
Disassembly Pattern Recognition
Given x86-64 disassembly, identify the high-level construct: prologue, for loop, strcmp check, null guard, heap alloc. 15 challenges — train your eye to flip between C and machine code.
15 challengesbegin.reKerberos
Animated AS, TGS, and AP exchanges. Inspect packet fields, dissect ticket anatomy, explore delegation flows, and learn five key attack techniques.
6 sectionsCOMplexity
Explore Windows COM from vtables and reference counting to apartments and HRESULT decoding. Step through the full object lifecycle.
6 sectionsCircle of Fifths
Explore key relationships, chord progressions, and scales on an interactive wheel. Includes quiz mode.
Theory & Quiz✎ Add a Question
Your Questions
0 questionsCelebration Animations
Click to fire any animation. They can stack.
⚠ XP Injection
Grants 100 XP instantly. You will be permanently tagged as a cheater. There is no undo.