malignant deity, baleful, noxious, strike dead
煞 centers on a destructive, deadly force: a malignant deity or baleful influence that strikes dead. The noxious quality is the harmful nature of such a force.
煞 is a character of uncertain origin. It visually contains 刍, 攵, and 灬, but the historical development of these components into the meaning of a malignant deity or striking dead is unclear.
The top part 刍 looks like a twisted, ominous figure, and 攵 suggests a striking action, while the bottom 灬 (fire) adds a destructive, baleful force. Together they evoke a malignant deity striking dead with noxious power.
For サツ, imagine a sudden, deadly strike that sounds like a sharp 'satsu'—like a swift, fatal blow from a malignant deity.