General Strategy:
Ideally, you want to get Gwen and Arthur up to level 5 asap. Try to bond Cassandra and Riordan as much as possible for a Sapphire later on. Simply fight within 2-3 tiles of each other in combat (spells do not count; however, Riordan's pet ability should).
Objectives:
Sword Rune x1
Gold x1000
Chests:
Elixer of HP x1
Enemies:
none