New Creeper variant - The Stalker

The Stalker, a smaller variant of the Creeper that only spawns in the deepslate layers of the world, appearing to blend in with the deepslate around it (or tuff as it could also be something in a trial chamber). They would stand at slightly over a block tall and have glowing beady eyes that pierce through the darkness in caves, watching the player from afar. When approached, the Stalker runs away to hide, only reappearing after a minute to continue stalking. When the player hasn't looked in their general direction for at least 5 minutes, the Stalker makes its move and sprints towards them with an explosion that flings the player more than damages them. 

The player would be able to hear the Stalker sprint since they have quick but loud footsteps. The Stalker would avoid light sources, like how Piglins avoid warped fungi, and would also have half the health of a regular Creeper to balance out its smaller size and agile speed.

As for drops, it could drop gunpowder like a regular Creeper. Could even have its own special drops from being killed by a skeleton.
In-game concept of the Stalker