This will vary across regions. In the DACH region, Roland Berger runs an electronic intelligence test. This test spans three categories, each divided into three sets of questions:
- finding word pairs
- completing word sequences
- completing sentences
- completing number sequences
- inserting mathematical operators
- calculating in your head
- assembling cut-up figures in your head
- rotating dice in your head
- completing matrices
Your result will be benchmarked (I think) against a sample of high schoolers. Your relative ranking will determine whether you passed or didn't. People seem to struggle the most with the matrices, the rest is more than doable with preparation.
However, during my 1st round interviews, I was told that they are phasing out the intelligence test and replacing it with an adaptive aptitude test comparable to the GMAT. I advise checking back with HR about what type of test you will be facing.