306.5b A planeswalker is treated as if its text box included, “This permanent enters the battlefield
with a number of loyalty counters on it equal to its printed loyalty number.” This ability creates
a replacement effect (see rule 614.1c).

706.2. When copying an object, the copy acquires the copiable values of the original object’s
characteristics and, for an object on the stack, choices made when casting or activating it (mode,
targets, the value of X, whether it was kicked, how it will affect multiple targets, and so on). The
“copiable values” are the values derived from the text printed on the object (that text being name,
mana cost, color indicator, card type, subtype, supertype, rules text, power, toughness, and/or
loyalty), as modified by other copy effects, by its face-down status, and by “as . . . enters the
battlefield” and “as . . . is turned face up” abilities that set power and toughness (and may also set
additional characteristics). Other effects (including type-changing and text-changing effects), status,
and counters are not copied.