Legion Reconsecrator is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Whenever Legion Reconsecrator attacks, exile up to one target creature card from a graveyard. If you do, conjure a duplicate of it into your graveyard. The duplicate perpetually becomes a black Skeleton with base power and toughness 3/1 in addition to its other colors and types. When Legion Reconsecrator dies, return another target creature card with power or toughness 1 from your graveyard to the battlefield.