I’m near the end of the game, at the pipes puzzle in the trial of blood. I’ve read a guide. I put blessed blood on the grate before the altar, then I interact with the altar and pick the second option.

The game goes into an overhead view of the grid on the floor. In the bottom right corner of the hud it says O Quit Puzzle. If I press circle I go back to the altar. If I press square the little interaction menu comes up with an “attack” option, which doesn’t do anything.

No other button seems to do anything. Is this bugged? Am I missing something? I’m playing on PS4.

I don't know about PS-4 but after getting the overhead view, adjusting the blocks for flow patterns, then hitting "end" ("O" in your case, I presume), you still have to select the first option on the alter to complete the puzzle. You should hear stone grinding on stone after the three colors move to their respective colors on the other end.

In the controller UI, once you get into the puzzle use the left stick to highlight blocks with the pointer, and then the X button to rotate the selected block (A with an Xbox compatible controller).

Thanks for the help, my problem was that the cursor was really small and starts right at the bottom of the screen so I couldn't see it. And while pressing random buttons on the controller to work out what exactly I'm supposed to be doing some of those buttons actually make the cursor disappear.

It was a fun little puzzle to solve once I figured out how to actually interact with it, nice little break from the usual gameplay.