question about orb of x spell.

[isildur]

can i take weapon focus(orb) just like ray?

does it take -4 on attack roll, when i using a orb spell against an enemy who is in melee combat with an ally of mine?

can i make critical hit by orb of x?

[Spuddles]

Yes to all except that it's actually Weapon Focus: Ranged Spells (ranged spells that require an attack roll vs. touch AC) or Weapon Focus: (Melee) Touch Spells.

Melf's Acid Arrow, Orb of Fire, and Scorching Ray are all Ranged Spells with attack rolls and are all covered under the same weapon focus feat.