Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Dark, with a dash of dark wit
Things get pretty dark when Elesin's ritual is interrupted and he is taken prisoner. Who would think that preventing death would touch off a story's most depressing moments? And hey, it's a pretty serious play over all, what with dealing with weighty topics such as colonialism, war, death, and spirituality. So yeah, there's a lot of darkness in the mix and the tone totally—and appropriately—follows suit.
That said, Soyinka definitely manages to sneak in some flashes of humor and wryness. Even when Elesin is imprisoned and wearing chains, some of his phrasing is darkly humorous.
For instance, when Simon asks Elesin for his "word of honour" that he won't try anything "foolish" when Iyaloja comes to visit, Elesin's incredulous response is "Honour? White one, did you say you wanted my word of honour?" When Simon responds by asking Elesin to promise not to receive anything from her, the disgraced horseman grows even bolder, saying: "But I am sure you have searched her clothing as you would never dare touch your own mother. And there are these two lizards of yours who roll their eyes even when I scratch" (5.65-68). Touché, Elesin.
We wouldn't say these comments are funny, exactly, but instead that in their quick wit, a sort of pointed humor emerges in the play. Elesin may be physically bound, but his mind and his mouth move quickly, stinging his captor in a way that, as readers and viewers, is hard not to delight in.