The term "most sphinxlike" refers to something or someone that is mysterious, enigmatic, or inscrutable in nature. The antonyms of this phrase could include words like open, transparent, accessible, approachable, and clear. These words describe things that are easy to understand, straightforward, and easy to approach. For instance, an open book is something that is transparent and easy to read, while an accessible pathway is easy to access and easy to navigate. By choosing to use these antonyms, one can effectively communicate a sense of clarity and openness, as opposed to the mysteriousness and ambiguity associated with "most sphinxlike.