Highlander

Highlander is a Constructed variant which allows only one copy of each card in the deck, with the exception of basic lands.

Rules

Any card from Alpha up through the latest Magic set can be used (except for banned cards). Cards from the Portal sets, International Collector Editions, and Championship decks can be used provided you put all your cards in opaque sleeves and the International Collector Edition card edges are rounded.
Special mulligan rule: From your first hand (that is, before any paris mulligan), you may remove any number of cards from the game, this may not be the entire hand. For each card removed from the game this way, you may draw a card. Then, all removed card are played at the bottom of your library in the order in which they were removed. No abilities are triggered by any of these actions.

A deck may not contain two card's with the same english name except basic land cards.
A deck must contain at least 100 cards.
Some cards are entirely banned in tournament formats. Since these are non-DCI-tournaments, they have individual ban lists, e.g. http://www.highlandermagic.info/index.php?id=bannedlist.
No sideboards are used.