Plant-Type Big Shot: Did My Golden Finger Run Away from the Start?

After transmigrating to another world, he finally got his golden finger, only for it to run away?

Thankfully, this golden finger had some decency and left him compensation.

It's only supposed to be a tough iron tree, so why does yours explode?

It's only supposed to be a flower for decoration, so why can yours heal your allies?

It's only supposed to be a mushroom to eat, so why does yours release poison?