This is an epic destiny I wrote to get a feeling for 4th ed game design. The basic idea is "more class powers than anyone else". In a way, it's the Anti-Divine Seeker ("powers from everyone else"). Opinions welcome.
True Master
Some say the spark of the True Master is shown already when a young boy or girl picks up a sword or spellbook the first time. Some say that true mastery is only achieved by hard work and dedication. There is no doubt that many aspire it, but few ever reach it. Those who do reach a deeper understanding of their class than lesser students could ever hope, and they will know a much broader range of powers than any one else. They become legends of their craft, masters that are sought out by students from near and far, and who's legend will be carried on.
Immortality
True Masters and their teachings live forever in the students they train, and the students of their students. They become part of the eternal chain that carries a tradition from generation to generation. When their physical body perishes, it is their legend that will carry on.
Prerequisites: 21st level, not multiclassed
Powers
21st level: Add an at-will attack power, an encounter power, a utility power and a daily power from the heroic tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +4 bonus to hit with your chosen encounter power.
24th level: Add an encounter power, a utility power and a daily power from the paragon tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +3 bonus to hit with your chosen encounter power.
30th level: Add an encounter power, a utility power and a daily power from the epic tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +2 bonus to hit with your chosen encounter power.
Demonstration of Perfection
Utility, Level 26
Free Action, Encounter
Choose one enemy. The next time you hit that enemy with an attack during this encounter, the attack is treated as a critical hit.
Special: You can regain this power as a free action by spending an Action Point.
True Master
Some say the spark of the True Master is shown already when a young boy or girl picks up a sword or spellbook the first time. Some say that true mastery is only achieved by hard work and dedication. There is no doubt that many aspire it, but few ever reach it. Those who do reach a deeper understanding of their class than lesser students could ever hope, and they will know a much broader range of powers than any one else. They become legends of their craft, masters that are sought out by students from near and far, and who's legend will be carried on.

Immortality
True Masters and their teachings live forever in the students they train, and the students of their students. They become part of the eternal chain that carries a tradition from generation to generation. When their physical body perishes, it is their legend that will carry on.
Prerequisites: 21st level, not multiclassed
Powers
21st level: Add an at-will attack power, an encounter power, a utility power and a daily power from the heroic tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +4 bonus to hit with your chosen encounter power.
24th level: Add an encounter power, a utility power and a daily power from the paragon tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +3 bonus to hit with your chosen encounter power.
30th level: Add an encounter power, a utility power and a daily power from the epic tier to your repertoire. These powers must be on your class list, and you may not choose a power you know already. You gain a +2 bonus to hit with your chosen encounter power.
Demonstration of Perfection
Utility, Level 26
Free Action, Encounter
Choose one enemy. The next time you hit that enemy with an attack during this encounter, the attack is treated as a critical hit.
Special: You can regain this power as a free action by spending an Action Point.