A Giant Red Basilisk. It will assist in battle by attacking often.
The mighty cockatrice. It can poison or petrify an opponent, while occasionally boosting your speed in battle.
An elusive Great Dragon. It can assist in battle with powerful dragon spells.
A mighty griffin. It can assist you in battle by improving your critical hit rate, while casting dragon magic.
A great undead golem. It will assist you in battle by granting and restoring ward.