Thunderous Smite
Your strike rings with thunder that is audible within 300 feet of you, and the target takes an extra 2d6 Thunder damage from the attack. Additionally, if the target is a creature, it must succeed on a Strength saving throw or be pushed 10 feet away from you and have the Prone condition.
Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 1.
Thunderous Smite 5.5e 2024 vs. 5e 2014 edition differences
The 2014 version triggers on the first hit during the duration, dealing 2d6 thunder damage and possibly knocking the target prone. The 2024 version's effect occurs immediately upon casting, with damage fixed at 2d6 (plus 1d6 per spell slot above 1st), and the prone condition is explicitly applied.