What the Heck Do You Call this Creature?

During our Banaue Holy Week vacation just a few weeks ago, at the garden of this hotel that we checked in, I stumbled upon this plant having these strange fruits that seem like thorned balloons. According to my creative imagination and very fast analysis, it's like a fusion between a sea urchin and a green golf ball. It's hollow and seems harmless though.

Up until now, I still can't digest into my system that such plant like this ever exist (in the country, at least) so I decided to blog about it in case I have some botanist readers who happen to know what this strange little plant is called. For the meantime, let me call it "Steven Sea-golf" (laughs).