Forum:Sakuretsu Armor and Using Effect Monsters' Effects More Than Once

Question #1 Sakuretsu Armor: Trap Card Activate only when your opponent declares an attack. Destroy the attacking monster.

Since this card never said it NEGATES the attack of the attacking monster... Does this mean that the attacking monster's attack still goes through? Meaning it will still be able to destroy a monster or attack the opponent directly if he or she controls no monsters?

Question #2 There are a many Effect Monsters out there that says "Discard 1 card...; Pay 1000 life points to... Tribute 1 monster on the field to...; etc." Like for an example, Tribe-Infecting Virus (Effect Monster) Discard 1 card from your hand and declare 1 Type of monster to destroy all face-up monsters of the declared Type on both sides of the field.

This card said to "Discard 1 card" to use the effect. I have seen many players use this effect more than once on the same turn, as in discarding more than 1 card to declare more than one type of monster in order to destroy many monsters at once. I mean this card does not say "This effect may only be used once per turn." So does this mean one may use this effect as much he or she wants as long as they discard 1 card? There are effect monster cards out there too that I have seen players use the effect multiple of times on the same turn, regardless if the cards specific says to discard 1 card to use the effect. Cannon Soldier may be used as an example to.

May someone clarify this for me?