The Magic: the Gathering (MTG) set Invasion (INV) was released on Oct 2nd, 2000. It includes 3 token cards.
Invasion is the first MTG set to include Player Reward tokens. The Magic: the Gathering Player Rewards program was used by Wizards to promote their DCI tournaments. Tokens were given as gifts to anyone who qualified for multiple tournaments, at this time very few tokens existed in the Magic world.