Summary
The Light Force is a powerful energy source that dwells inside Princess Zelda in The Legend of Zelda: The Minish Cap. Vaati drains most of it, thus turning himself into a powerful being. In appearance, it looks not too unlike one of the three component golden triangles that make up the powerful relic known as the Triforce. In this case, it appears as a single golden triangle and acts as a source of near limitless magical power, although just how powerful the Light Force is compared to the might of the Triforce is presently unknown.
According to the Hyrule Historia, the Light Force is actually a huge amount of the force that dwells within all beings.
Powers and Stats
Tier: Unknown. Possibly up to High 5-A
Name: The Light Force
Origin: The Legend of Zelda
Type: Magical Energy Source
Powers and Abilities: A source of "infinite power"
Attack Potency: Unknown. Possibly up to Dwarf Star level (Comparable to a single piece of the Triforce given it's description of possessing "Infinite Power" [An obvious NLF, but it does give the Light Force similar weight in terms of importance in the Zelda Universe])
Wielder(s): The Hero of Man, Princess Zelda (Minish Cap), Vaati (Not the entirety of it, but a significant fraction after extracting it from Princess Zelda)
Material or Element: Magic known as "The Force"
Needed Prerequisite for Use: You just need to possess it to gain access to its power
Notable Attacks/Techniques or Alternate Forms: