Monsters your opponent controls lose ATK equal to the combined ATK and DEF of the monsters revealed by this effect
If the target spell has a variable number of targets, you can't change how many targets it has
If a card(s) is destroyed, you can Special Summon it from the Hand, then add a monster from the deck to the hand that is the same as any monster in the Extra Deck, GY, or Banished that was destroyed that turn
The 10 damage is irrelevant, but preventing your opponent from playing Item cards from their hand is almost game breakingly good
4 Mitsurugi And Ryzeal Rituals And Robotics Mitsurugi and Ryzeal may seem like completely different archetypes, but they interact together like a pendulum swinging back and forth
Getting Into the Archetype Galvanic Discharge is too good to be confined to UR/RW decks, so seeing that late is more of a red signal than anything else