Reaction: this is Greninja’s moveset instead of what we have now;
B: Bubble; Greninja quietly blows 3 bubbles that can trap opponents. Said bubbles are popped by the opponent escaping or being attacked.
B + Forwards: Water Shuriken
B + Up: Smokescreen; Greninja disappears in a puff of smoke that can trip opponents
B + Down: Shadow Sneak