Ivysaur - 002 - There is a plant bulb on its back. When it absorbs nutrients, the bulb is said to blossom into a large flower. When the bud on its back starts swelling, a sweet aroma wafts to indicate the flower's coming bloom.
They should release Pokemon red and blue on virtual console and make it so you can transfer from those games to X and Y. Just so people who didn't know about the events can actually obtain a mew* for their pokedex *(see mew glitch Pokemon)