They have the same mechanics. Immunity to spells; one being of 3rd level one of 4th. Also you have to choose certain spells for one and the other gives you blanket immunity of all spells. Mechanically they still work the same.Elder-Basilisk said:I believe that you're mistakenly interpreting the precedent here. Spell Immunity and Minor Globe of Invulnerability have radically different mechanics. Spell immunity grants immunity to specific spells that have to be level x or below. Minor globe of invulnerability grants immunity to all spells of 3rd level or lower. With Spell immunity, the determining factor is the spell's name. That the spells must be lower than level 5 is merely a restriction on which spells can be chosen. Minor Globe of invulnerabilities protection is much broader but is directly contingent upon spell level.
A heightened Magic Missile is still a Magic Missile. A Shield spell would still stop it. A brooch of shielding would still absorb it. Consequently, as a DM, I would rule that Spell Immunity still protected against it--even if it were heightened to 5th level.
But brooch of shielding doesn't say Magic Missles of less than x level. Spell Immunity "asks" two things when a spell is cast at the protected target. "Is this a spell chosen at casting time? Yes/No" and "Is this a 4th level spell or less? Yes/No" If either of those is "No" Spell Immunity won't stop it.
On the other hand, a heightened 5th level Magic Missile is no longer 3rd level or lower
Exactly my point.