You can find Reanimal's secret code in Chapter 1: Dead in the Water. However, note that the secret code is the same in every game, so if you've already passed this chapter and just want the answer, go ...

The Reanimal secret code is, as you’d expect, a secret, but Tarsier Studios has gone out of its way to tuck this one away in a spot you wouldn’t necessarily think to look. It took me quite a bit of ...