Start Card (スタートカード Sutāto Kādo) is a keyword ability that allows a player to put the card with this ability on their own Player Square during the game preparation.
All cards with this ability are Cost 3 Z/X with Power 5000 or less. If a Start Card has another ability, the ability is usually a single startup ability that can only be used if the card in question is in the Charge.
Start Card itself is not a mandatory part of a deck (you may have more than one Start Card in the deck or even didn't bring any) and a player may choose to not put a Start Card during the game preparation even if they has it in the deck. The current text of Start Card ability is shown below: