Tap
Tap is an keyword action that is usually represented on cards with 
symbol. The tap symbol was introduced on cards in the 4th Edition.
Tap symbol
The tap symbol has undergone 2 changes. Originally the symbol was a tilted T. In 4th Edition, it was changed to a curved arrow with a tilted rectangle representing the tapping card. In 8th Edition, it was changed to a curved arrow without the rectangle behind it .
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Actions that cause a card to tap
- Using its activated ability if that ability requires it to tap
- Declaring a creature as an attacker (see Declare Attackers Step)
- Regenerating
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