as an action, you summon a 10-foot tall and 20-foot wide wave of water that travels 50 feet in a straight direction and an identical wave is summoned and travels in the opposite direction, any creatures in the way of this wave must make a str/dex/con save with a dc of (10+ your chr modifier), if they succeed, nothing happens. if they fail, they are knocked prone, are poisoned and take 1d10 acid damage.