A fantasy football dynasty league is a format that challenges you to play more like you own a real NFL team. The expectation when joining a dynasty league is that you will draft your team and then keep most, if not all, of your players for several years. The strategy involved is very different than redraft leagues because you have to think about each player's value far beyond just the current season. A player's value decreases over time due to age and expected decline in fantasy production. Each offseason you'll have the opportunity to participate in a rookie draft to rebuild or reinforce your roster.
You can find dynasty draft cheat sheets here.
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