Ultra-sun: Its nature is to store up electricity. Forests where nests of Pikachu live are dangerous, since the trees are so often struck by lightning.Moon: It’s in its nature to store electricity. It feels stressed now and then if it’s unable to fully discharge the electricity.Alpha-sapphire: This Pokémon has electricity-storing pouches on its cheeks. These appear to become electrically charged during the night while Pikachu sleeps. It occasionally discharges electricity when it is dozy after waking up.
Prof. Lotus' Notes: Pikachu is a portmanteau of two Japanese onomatopoeia, first being 'Pika Pika' - Which means to Sparkle and 'Chu Chu' - the sound that mice make.
Gender Differences: Female's tail ends in the upper half of a heart. Male Pikachu have squared off tails