If card text instructs players to repeat an effect, the entirety of the effect resolves again, including the text to repeat the effect. If the card that is creating a repeating effect is removed from play, the effect can no longer repeat.
Cards with the text "trigger this effect again" will also repeat the entire effect, including the text to trigger the effect again.
Note: Repeating an effect does not interact with the Rule Of Six as the Rule of Six only applies to playing or using cards, not triggering their effect multiple times.
See also: Preceding