Egyptian God Phoenix
Egyptian God Phoenix (or "The Winged Dragon of Ra's" "Phoenix Mode") is one of three forms of "The Winged Dragon of Ra" which the latter can transform itself into at the cost of 1000 Life Points if Special Summoned from the Graveyard. In this form, "The Winged Dragon of Ra" cannot be removed from he field except by its own effect (a Divine-Beast is sent to the Graveyard at the end of the turn it is Special Summoned, in the Anime).
Yu-Gi-Oh!
The most well-known effect of "The Winged Dragon of Ra's" Phoenix Mode is that any monster that battles with it will immediately be destroyed without even applying Damage Calculation (note: thanks to Ra's Instant Attack ability, this allows Phoenix to attack and destroy all the opponent's monsters). This effect was used by Marik Ishtar during his battles with Joey Wheeler (to destroy Joey's "Gilford the Lightning" in Ep.127) and Yugi Muto (to destroy Yugi's "Slifer the Sky Dragon" in Ep.139 and again in a failed attempt to destroy his Obelisk the Tormentor in Ep.141).
Yu-Gi-Oh! GX
This effect was also used on Jaden in Yu-Gi-Oh! GX by Franz in Ep.085. It reversed right away to its original mode and did not stay in that mode for an entire turn. It was also treated as an effect rather than an attack. It allowed the user to destroy all the opponent's monsters at the cost of 1000 Life Points.
