Yes, we know, you can’t odd. Wait, that’s not the saying.

Zero is even, so you can attack with zero creatures. One, however, is odd.

To double a creature’s power, that creature gets +X/+0, where X is that creature’s power as Rule with an Even Hand’s last ability resolves.

Conspiracies are never put into your deck. Instead, you put any number of conspiracies from your card pool into the command zone as the game begins. These conspiracies are face up unless they have hidden agenda, in which case they begin the game face down.

A conspiracy doesn’t count as a card in your deck for purposes of meeting minimum deck size requirements. (In most Limited formats, the minimum deck size is 40 cards.)

You don’t have to play with any conspiracy you draft. However, you have only one opportunity to put conspiracies into the command zone, as the game begins. You can’t put conspiracies into the command zone after this point.

You can look at any player’s face-up conspiracies at any time. You’ll also know how many face-down conspiracies a player has in the command zone, although you won’t know what they are.

A conspiracy’s static and triggered abilities function as long as that conspiracy is face up in the command zone.

Conspiracies are colorless, have no mana cost, and can’t be cast as spells.

Playtest cards aren’t legal for play in any tournament format other than Mystery Booster Limited formats. On the other hand, we expect they will spice up a wide variety of non-tournament games (as long as everyone’s on the same page about using them!).

Playtest cards use a modified version of game symbols, such as {T} and {W}. These modified symbols should be treated as the standard symbols during play.

For many playtest cards, you’ll need to make a generous assumption that basic game rules would be updated to allow them to work. The Mystery Booster 2 Playtest Card Notes section (reproduced here in individual Gatherer rulings) provides guidance for fitting these cards into the existing rules structure.