Better be safe and give credit where it's due. (Though would the scallywags responsible for the in-game graphics be Graphic Designers or Artworksmen?)
EDIT: As an encore, here's a loose sample of stonework from that Minish Cap game.
Well, beta 12.999 lets you import your own sound effects, so I'd like to be the first to contribute some aural snippets, plundered from their respective games for the good of NeoFirst.
Note: these are 16-bit waves, so they might or might not be useful in their present state.
Sword Beam (from BSZelda)
Fire Rod (from LA)
Ice Rod (from LttP)
Sword Beam and other magic effects (from LttP)
Bomb Blast (from LttP)
Shutter Bang (from BSZelda)
Item Jingle (from BSZelda)