Digimon: Digital Monsters

In a dream, Ken reminisces entering the Digital World for the first time and becoming resentful towards his older brother, Sam. When Sam dies, Ken receives an e-mail leads him to becoming the Digimon Emperor. After waking up, Ken returns to the Digital World and ends up in Primary Village where, after promising to redeem himself, he is reunited with Wormmon in his infant form Leafmon.