1) In Norse mythology, Valhalla is a majestic hall located in Asgard, the realm of the gods. It is the afterlife destination for brave warriors who die in battle, where they are greeted by the Valkyries and engage in feasting, drinking, and preparing for the final battle of Ragnarok.

2) The first video game console, the Magnavox Odyssey, was released in 1972 and featured games such as Pong and Table Tennis.

3) The word "piano" contains three vowels: I, A, and O.

4) The word "elephant" contains three vowels: E, A, and E.