OLL 12
The algorithm, how to recognise it and how to practise it without cheating.
Recommended algorithm
M' R' U' R U' R' U2 R U' R r'12 moves
How to recognise it
A small lightning bolt: the back and right edges with the back-left corner. The front-left corner's yellow faces you.
Its inverse is another case
Do the 12 algorithm backwards, r R' U R' U2 R U R' U R M, and you are solving 5.
That's why CubeDojo never scrambles 12 that way: it builds a random state with the case fixed, so you practise 12 and not 5.
Practise 12 now
Random-state scrambles, a timer and spaced review. Free, on the web and on your phone.