Evil HERO Malicious Fiend

 This card is the first Fusion Monster to specify the Level of a Fusion Material.

---

Curiously, this monster is thinner than Evil HERO Malicious Edge despite being a more powerful version of it.

---

This monster appears to be a fusion of Evil Hero Malicious Edge and Evil Hero Infernal Prodigy, as it has the former's claws and body armor and the latter's wings.

---

Ironically, Infernal Prodigy cannot be used as a Fusion Material, as it requires a Level 6 or higher Fiend monster as the second Fusion Material for this card’s Fusion Summon.

---

Alternatively, this monster could be a fusion of Evil Hero Malicious Edge and Evil Hero Inferno Wing.

---

They are both FIRE monsters.

---

Inferno Wing is a Level 6 Fiend monster. Unlike Infernal Prodigy, it could be used as a Fusion Material to summon Malicious Fiend.

---

Malicious Fiend has 2100 DEF. This matches with Inferno Wing's ATK, also 2100.

---

They both have spikes on their heads (Inferno Wing has spiky hair, while Malicious Fiend has literal claws on the head).

---

They both have wings and prominent claws on their hands, although their wings and claws aren't really similar.

---

Both have their eyes masked in some way (Inferno Wing by a visor and Malicious Fiend by a helmet).

---

OCG Rulings

---

"Must be Special Summoned with "Dark Fusion" and cannot be Special Summoned by other ways." is not treated as an effect.: Evil HERO Malicious Edge

The "During your opponent's Battle Phase, all monsters they control are changed to face-up Attack Position, and each monster they control must attack this card, if able." effect is a Continuous Effect.

Even if this effect is being applied, your opponent can choose whether conduct their Battle Phase or not. (If they conduct their Battle Phase, each monster they control must attack this card.)

This card can only be Special Summoned by "Dark Fusion" or "Dark Calling". After this card is Special Summoned, if it is sent to the Graveyard, it cannot be Special Summoned with "Monster Reborn".

The effect of "Evil HERO Malicious Fiend" is applied from the Start Step of the Battle Phase onward. The effect is applied throughout the Battle Phase.: At what time do you apply the effect of "Evil Hero Malicious Fiend"?
Monsters Special Summoned during the Battle Phase are also changed to Attack Position.
After "Goblin Attack Force" changes to Defense Position, you must apply the effect of "Evil HERO Malicious Fiend" and switch "Goblin Attack Force" back to Attack Position.

If you control both "Evil HERO Malicious Fiend" and an "Evil HERO Lightning Golem" equipped with "Ring of Magnetism", and their effects are being applied, all monsters your opponent controls are changed to Attack Position, and they must atack. Since the effect of "Ring of Magnetism" is being applied, all monsters your opponent controls must attack "Evil HERO Lightning Golem" equipped with "Ring of Magnetism".: If the effects of "Evil Hero Malicious Edge" and a "Ring of Magnetism" are being applied, which monster can be attacked?

If you control both "Evil HERO Malicious Fiend" and "Belial - Marquis of Darkness", and their effects are being applied, all monsters your opponent controls are changed to Attack Position, and they must atack "Evil HERO Malicious Fiend

Previously Official Rulings

Your opponent does not have to conduct their Battle Phase. If your opponent does not conduct their Battle Phase, "Evil Hero Malicious Fiend's" effect is not applied.

"Evil Hero Malicious Fiend's" effect is applied at the start of your opponent's Battle Phase and remains activate{{sic for their entire Battle Phase. Monster Special Summoned during your opponent's Battle Phase will be affected. If a monster's Battle Position is changed to Defense Position at the end of the Battle Phase ("Goblin Attack Force", etc.), it will be shifted into Attack Position.

If you have 2 or more "Evil Hero Malicious Fiend" when your opponent attacks, you decide which "Evil Hero Malicious Fiend" is attacked.

Only monsters that are able to attack must attack "Evil Hero Malicious Fiend". If you have "Swords of Revealing Light" and "Evil Hero Malicious Fiend" on your side of the field, your opponent's monsters are unable to attack, so they cannot attack "Evil Hero Malicious Fiend". If you have "Gravity Bind" and "Evil Hero Malicious Fiend" on your side of the field, your opponent's monsters of Level 4 or higher are unable to attack, so they cannot attack "Evil Hero Malicious Fiend".

If "Level Limit - Area B" is face-up on the field, when your opponent starts their Battle Phase their Defense Position monsters are still shifted into Attack Position and must attack "Evil Hero Malicious Fiend". If "Level Limit - Area B" is being negated and then during the Battle Phase its effect is reapplied, the opponent's Level 4 or higher monsters are shifted into Defense Position and are unable to attack.

If your opponent's face-down Flip Effect Monsters are flipped simultaneously by "Evil Hero Malicious Fiend's" effect, their effects start a Chain. (refer to Simultaneous Effects Go On Chain.)