There appears to be many variations of possess skills. I thought I\'d organize your ideas here:
Variation 1:
Person with possess skill has a weakened true form (pitiful speed, very low hp). However, the person can take over the body of a monster/critter and immediately assume that body instead (so the true body is replaced). Should the monster die, the possessor escapes from the possessed body and exposes his/her vulnerable true form. There is a delay before the possessor can take over another body. This delay makes it so that you cannot abuse the skill by simply committing suicide and possessing another monster.
Monsters that can be possessed must have lower levels than you. However, when you\'re more specialized in possessing, you may obtain bonus stats such as enhanced monster skills and passive stats.
Variation 2:
The possessor has a regular original body. When he/she uses possession on another monster, only the player?s mind is transferred to monster. The tradeoff is that if the possessor?s true body is killed, the mind is also killed.
Variation 3:
You can possess the weaker monsters, but that just makes the monster switch sides. It plays more like an enchanter in EQ.
