|Vulnerable to||PSI Fire|
- "A lot of fertilizer and miracle-grow did nothing for this guy. Watch its eye - you may get Diamondized."
- — Description
- "I am the guardian of Milky Well. For millions of years, I've been cursed to be a sprout. For millions of years, I've had to observe other fauna grow and die, while their children move on to other fields. I've endured my loss of friends, so too, shall you endure my own pain. Gaze into my eyes, and I'll see diamonds."
- — Trillionage Sprout
Trillionage Sprout is the guardian of the third "Your Sanctuary" location in EarthBound, Milky Well. The Trillionage Sprout is aided in battle by two Tough Mobile Sprouts, which can heal the Trillionage Sprout with LifeUp. This boss is the first enemy encountered by Ness and co. that can Diamondize party members, and is one of the very few enemies who can do so.
Its name is a contraction of the phrase 'Trillion age', in reference to its appearance: a withered sprout that has evidently survived for a relatively long span of time without maturing.