Wondering if this would work:
1) Put an invisible octarok on a solid tile and make it so when there is only one space he walk onto
2) Surround him with 'pit' combos & turn off the tile warp.
3) Now, draw an animated tile of a Deku plant and make a combo for it, set its type to slash or, possibly better yet, a "Bush" type.
4) Place it over where the octorok goes.
5) Set the "Invis. Enemies" screen flag!
Now you have a Deku that will repeatedly shoot rocks (although in one direction only)