Hogwarts Legacy is a massive open world with many side activities to do whenever you're finished attending class, of course. Going to classes will introduce you to a different companion and professor. As your character is trying to catch up to the other 5th years, the professors are doing what they can to help.
After attending a class, you'll sometimes receive extra assignments from the professor that revolve around whatever was taught in class. These assignments help you understand the gameplay significance of the new system introduced in the class while also sometimes giving players access to a new spell. Bombarda is the reward for completing Professor Howin's Assignment.
Completing Professor Howin's Assignment
While you attend your first Beast Class earlier in the game, this quest is unavailable until after you have completed the second trial Charles Rockwood's. After completing this trial, the player will receive an owl, and Professor Howin's assignment will be available in your quest menu. This assignment has you traveling and catching two different Beasts, both conveniently marked on your map when tracking the quest.
One of the beasts players will need to track down and capture is Diricawl. These are small bird-like creatures that can be relatively easy to catch. Head to the marked location on the map within the Hogwarts Valley and approach a small cluster of them on the outside perimeter of some ruins. Cast Levioso on the beast to briefly hold them in the air, and begin grabbing them with your nab-sack. After landing on the ground, if you haven't caught the beast, they will briefly dig into the ground, leading to a long time of them standing still, making for an easy catch. For this specific location, a few Inferi will spawn nearby around the tower, and players may get their attention during or after the catch, so be prepared with some fire spells.
Next, you will also need to collect a Giant Purple Toad. These beasts seem pretty self-explanatory, being just a large toad that's purple. This assignment does mark a location on your map in the middle of a swamp. It's recommended you stealth around this swamp, as many other larger and more aggressive frogs can be attracted and will quickly swarm the player with incredible numbers if you're not careful. This beast is slightly easier to catch and won't run away as fast, making it a much easier and safer catch.
Attending Class And Getting Bombarda
After completing the assignment, you'll be able to return to another beast class, where Professor Howin will teach you Bombarda after. This powerful attack can destroy objects and deal great damage in combat. This spell can also be upgraded to have a much wider area of effect and is well worth the point to use moving forward. This spell acts as a great AOE, helping keep enemies spread out or to be used in a combo to throw your enemies around and keep them from attacking.