ReachReach is a static ability.
A creature with flying can’t be blocked except by creatures with flying and/or reach. (See rule 509, “Declare Blockers Step,” and rule 702.9, “Flying.”)
Multiple instances of reach on the same creature are redundant. (CR 702.17),
vigilanceVigilance is a static ability that modifies the rules for the declare attackers step.
Attacking doesn’t cause creatures with vigilance to tap. (See rule 508, “Declare Attackers Step.”)
Multiple instances of vigilance on the same creature are redundant. (CR 702.20)
Ward Ward is a triggered ability. Ward [cost] means “Whenever this permanent becomes the target of a spell or ability an opponent controls, counter that spell or ability unless that player pays [cost].”
Some ward abilities include an X in their cost and state what X is equal to. This value is determined at the time the ability resolves, not locked in as the ability triggers. (CR 702.21) (Whenever this creature becomes the target of a spell or ability an opponent controls,
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) it unless that player pays
.)
When this creature enters, you gain X life, where X is the greatest power among Giants you control.