Monster Summoning Spells are earned by a particular class through a mutual trust between the class (typically druids and other nature lovers) and the summoned race. When a creature is summoned, it will appear in the same room as the spellcaster and then follow him/her/it.  Summoned monsters can be ordered to do tasks for the spellscaster (any legal command or social used in the game), the most important of which is the summoned creature's ability to kill for you and otherwise protect.

Adding as many and various summoned creatures to your group is a good strategy for spellcasters who can summon creatures.  The maximum number of followers a spellcaster may have is dependant on his Charisma. Spells that summon creatures are: Envoke Earth Elemental,  Summon Will-O-Wisp,  Summon Treant, Tentacles. 

Orders given to summoned monsters must be given one at a time, and must be spoken clearly and precisely, the consequences of such misunderstandings can sometimes be disasterous. Summoned monsters will stay with the spellcaster until you either abandon him, he dies, or you die (unless otherwise noted), trusting your judgement completely and never objecting to your actions.

Will-o-Wisp 

Class/lvl: Druid 4
To Cast: cast 'summon will o wisp'
Target: Will-O-Wisp
Duration: Instantaneous
Effect: Summons a will-o-wisp to the spellcaster's location. Will-o-wisp immediately starts to follow the spellcaster.
Mana: 30-60 (+2)

Appearing as small, dynamic forms of light, the will-o-wisps typically live in the deeper parts of enchanted forests. When encountered in the wild, will-o-wisps will behave irratically and either attack, harm, help or confuse any travellers, especially preferring to lead people astray from certain paths.

Will-o-wisps were the first race that the ancient druids befriended and with whom they joined forces with to protect the well-being of the Sacred Groves and other places of magic within the Realms. Since those ancient days, the will-o-wisps and druids have held firm to their agreement and work well together to protect each other's survival.

 Treant 
Class/lvl: Druid 22
To Cast: cast 'summon treant'
Target: Treant
Duration: Instantaneous
Effect: Summons a treant to the spellcaster's location.
Mana: 100-150 (+5)

Treants are strudy tree-men that can join with the druid's group and aid in battle and absorb quite a bit of damage. Goto the Treant's Race Page to view information on the trant's attributes and abilities. The Monster's Compendium also has useful information on treants.

The Treants were the second race to join the effort to save the Sacred Groves in the Realms.  Although uninterested in the ancient magic gathered in the groves, the areas in and around the groves were ancient relics in the Treant's history as well.  Determined to save the ever-growing danger pervading in the wilderness of of the Realms, Treants joined with the Druids and gave them the ability to call upon one of their own when in need.