How Vigilance works:

Vigilance is a static ability that affects creatures when they are declared as attackers. Creatures with vigilance do not become tapped when they are declared as attacking. This does not mean that tapped creatures can attack. Also, removing vigilance from an attacking creature will not cause it to be come tapped.

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How Trample works:

When assigning and dealing combat damage from an attacking creature with Trample, its controller must assign what would be lethal damage to all blocking creatures. Any damage in excess of this can then be assigned to the defending player. For example, if an attacking is blocked by two s, when the combat damage step begins […]

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