Suitable Mounts: You have the final decision on what is or is
not a suitable mount. At its most basic level, a mount should have
the following characteristics:
• Able and willing to carry its rider in a typical fashion. (A camel
is able and willing. A tiger might be capable but may not be
willing. A giant might be willing but not truly able.)
• At least one size category larger than the character. Also, a
flying mount can carry no more than a light load aloft.
• The mount’s Challenge Rating should be no more than 3 less
than the rider’s character level. If the mount can fly, its
Challenge Rating should be no more than 4 less than the rider’s
character level.
The accompanying tables (one for Medium riders, one for
Small riders) provide basic characteristics of creatures that can be
used as mounts.
DMG, 簡明扼要.
另外YY的東西3E, 3R不分, 很多東西要一個一個查...