The bonus of the Summoner gives them +20 experience points worth of creatures summoned every day. It functions like Basic Summoning, if the hero lacks the skill.
The Summoner is most likely to learn Life magic and Nature magic and fairly likely to learn the Scouting and Order magic skills. Summoners can not learn Death magic when leveling up unless some basic training in the skill is already known.
If the hero has a high Summoning skill, this bonus will help with growing an army over time, providing free troops every day. The extra creatures can be useful in battle.
The combination of two magic schools is also valuable in itself.
|Heroes of Might and Magic IV classes|
|Standard hero classes||Knight - Death Knight - Lord - Thief - Archer - Barbarian - Priest - Necromancer - Mage - Sorcerer - Druid|
|Advanced classes||Archmage - Assassin - Bard - Battle mage - Beast lord - Beastmaster - Cardinal - Crusader - Dark Lord - Dark Priest - Demonologist - Enchanter - Field marshal - Fire diviner - Fireguard - General - Guildmaster - Heretic - Illusionist - Lich - Lord commander - Monk - Ninja - Paladin - Prophet - Pyromancer - Ranger - Reaver - Seer - Shadow mage - Summoner - Warden - Warlock - Warlord - Witch king - Wizard - Wizard King|