The ornamental design for a puzzlecube, as shown and described.
FIG. 1 is a first perspective view of a puzzle cube, showing my design.
FIG. 2 is a second perspective view thereof.
FIG. 3 is a front elevation view thereof.
FIG. 4 is a rear elevation view thereof.
FIG. 5 is a left side elevation view thereof.
FIG. 6 is a right side elevation view thereof.
FIG. 7 is a top plan view thereof.
FIG. 8 is a bottom plan view thereof.
FIG. 9 is an enlarged view of an area labeled 9 in FIG. 1; and,
FIG. 10 is an enlarged view of an area labeled 10 in FIG. 2.
The even-length dash lines depict portions of the puzzle cube that form no part of the claimed design. The long-short dash lines depict the bounds of magnified portions and form no part of the claimed design.