Morph
From Dragon Quest Wiki
Morph (Originally Transform) is a spell in the Dragon Quest series.
Effect
Which ever ally the spell is used on allows the caster to take on the attack & defense power, as well as the spells of the target.
Appearances
Dragon Quest III
The spell is learned by both Mages and Sages at Level 37.
Dragon Quest IV
The spell is used by Eliza to pose as The Hero so that he/she won't be killed by Psaro the Manslayer's army. She demonstrates the spell earlier in the Prologue in the Sony PlayStation and Nintendo DS Version, in which she turned into a frog & rabbit.
It is also used by Float-o-copiers, but can be undone by use of the Zenithian sword and the Ra's Mirror.
The Hero can also learn it at Level 30, but only in the NES Version.
Dragon Quest VI
The spell is only usable by Devil glasses and Haunted mirrors.