2D Shooter

Your proposed modifications sound okay. Some things to be aware of in order to earn full points in them though: if you are making visual changes to the player and enemies make sure that you are making the sprites yourself if you want them to count for full points (each completely new sprite you make can count as one so long as you are putting your best effort into them), similarly for audio changes if you are making the new audio yourself each new piece can be a significant modification. For both of these if you are retheming the soundscape or visuals you can use things not made by you just make sure to replace everything and that the replacements fit some theme you are trying to achieve (completely retheming the art would be one significant modification and completely retheming the sound design would also be one). The dialogue additions would certainly be significant as the work to add that will be sufficiently substantial regardless of how you approach it (keep in mind you may use tutorials to do this change, we allow this as it is strictly beneficial to your speed of learning the things you are interested in)