Medieval verse form. 39 lines. Has to use the same six end words through out, in a pattern like so (reading downward):
| 1 | 6 | 3 | 5 | 4 | 2 |
| 2 | 1 | 6 | 3 | 5 | 4 |
| 3 | 5 | 4 | 2 | 1 | 6 |
| 4 | 2 | 1 | 6 | 3 | 5 |
| 5 | 4 | 2 | 1 | 6 | 3 |
| 6 | 3 | 5 | 4 | 2 | 1 |
So, yes, you have to find a new way to use six different endwords in each stanza. It ends with a 3-line envoy that uses 5,3,1; or possibly 5(2), 3(4), 1(6). It’s all in iambic, of course: either pentameter or tetrameter. The technical term for the entire process is ‘one big pain in the ass.’
But it’s in the can.