Petal can't be played. Cohorts only.
I'm trying to find the text that says this. Could you point it out?
MMIII, page 7[spoiler]"Level Adjustment
This line is included in the entries of creatures suitable for
use as player characters or as cohorts (usually creatures with
Intelligence scores of at least 3 and possessing opposable
thumbs). Add this number to the creature’s total Hit Dice,
including class levels, to get the creature’s effective character
level (ECL). A character’s ECL affects the experience the char-
acter earns, the amount of experience the character must have
before gaining a new level, and the character’s starting equip-
ment. See pages 172, 199, and 209 of the Dungeon Master’s
Guide for more information."[/spoiler]
MMI, page 7[spoiler]"Level Adjustment
This line is included in the entries of creatures suitable for use as
player characters or as cohorts (usually creatures with Intelligence
scores of at least 3 and possessing opposable thumbs). Add this
number to the creature’s total Hit Dice, including class levels, to
get the creature’s effective character level (ECL). A character’s ECL
affects the experience the character earns, the amount of experi-
ence the character must have before gaining a new level, and the
character’s starting equipment. See pages 172, 199, and 209 of the
Dungeon Master’s Guide for more information."[/spoiler]
The MMII doesn't address "cohorts" at all.
MMV, page 213[spoiler]"Level Adjustment: Certain monsters can used as the basis
for interesting, viable player characters. These creatures have
a level adjustment entry, which is a number that is added
to the creature’s total Hit Dice to arrive at its effective
character level. A creature that has multiple special abilities
is more powerful as a player character than its Hit Dice
alone indicate. For example, a kuo-toa’s level adjustment +3
indicates that a 1st-level kuo-toa wizard is the equivalent
of a 3rd-level character.
Level adjustment is not the same as an adjustment to a
creature’s Challenge Rating because of some special quali-
ties it possesses. Challenge Rating refl ects how diffi cult
an opponent is to fi ght in a limited number of encounters.
Level adjustment shows how powerful a creature is as a
player character or cohort in campaign play. For instance,
a drow receives a +1 adjustment to its Challenge Rating
to account for its special abilities, indicating that it’s
tougher in a fight than its Hit Dice would suggest, but
its level adjustment is +2 to balance its abilities over long-
term play."[/sub]
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