As long as you control Pennon Blade, its ability constantly counts the number of creatures you control. It doesn't matter who controls the creature it's equipping (in case an opponent somehow manages to take control of that creature). If you control the creature it's equipping, the bonus will include that creature too.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.