To get this, you just have to zap a particular mountain in the hub world with Thunder (
EDIT (4/19/2021): Once the cat starts talking, be sure to click through the text with
. If you cancel with
, the achievement will not unlock. (Thanks to DarkDragonEye7 for pointing this out, and Phil the Bear for confirming.) Btw, if you do accidentally cancel with
, just play any level, and when you're back to the hub world, the mountain (and cat) will be reset.
To find the mountain, go straight up the map from where you get the Thunder. You'll pass a desert island, then you should see the mountain on the next land you pass over. If you hit the level with the dino, you've gone too far.
Here's a quick video showing me stumbling across the mountain.