硬核

硬 = 更 + 石 : Maud Younger (y) finds the snake which ate too much (更) in the engine's bathroom ((e)ng4), and it feels miserable. To make the snake feel better Maud massages the snake using two warm stones (石). As Maud massages the snakebshe finds that the snake's belly is really hard (硬).

核 = 亥 + 木 : Hamlet (h) is unpacking the presents he found under the Christmas tree (木) in the elevator's kitchen (e2). He found lots of walnuts (核), but he doesn't know whether there are kernels or stones (核) inside. Fortunately he also unpacked a boar (亥) which sniffs at the walnuts and, after the careful examination (核), tells Hamlet what's inside.

核 = 亥 + 木 : Hamlet (h) is unpacking the presents he found under the Christmas tree (木) in the elevator's kitchen (e2). He found lots of walnuts (核), but he doesn't know whether there are kernels or stones (核) inside. Fortunately he also unpacked a boar (亥) which sniffs at the walnuts and, after the careful examination (核), tells Hamlet what's inside.