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What are Head & Body modes?

Titan Masters Attack introduces two new character modes that work together: head mode and body mode.
Cards with a head mode are placed above a character that has a body mode, combining them into a single character. The resulting character is a single character made up of both cards. The body mode card will tell you the character's stats and abilities, and the head mode card will give the character a bonus. That bonus may be an added ability or an increase to attack, defense, or health. Like other characters, that character starts the game in alt mode. If the character is KO'd, even if it's your last character card, the card with head mode is returned to the battlefield in bot mode. That bot mode character can't flip.
Source: Wizards of the Coast (2020-05-09)    【Link to Ruling】
Tags: Head, Body