At every Passover Seder, there is a Seder Plate that has many ceremonial items on it, like the Charoset, which symbolizes the mortar that B’nei Yisrael had to stomp to make bricks. If I could add a ceremonial ritual to the Seder, I would add something that represents the splitting of the Red Sea. When B’nei Yisrael was leaving Egypt, Pharaoh started to chase them. When they came to the Red Sea, B’nei Yisrael thought that they would be captured, but then a miracle happened! G-d split the Red Sea in two, and B’nei Yisrael escaped from Pharaoh’s clutches. I would add a ritual to the Seder where everyone pours a little bit of water onto a plate, and then they take a piece of matzah and use it to push the water to opposite sides of the plate. Then they eat the matzah. This would represent the splitting of the Red Sea and also, by eating the soggy matzah, we would remember that B’nei Yisrael did not get wet when they crossed through the sea.