Aes Sedai are far from defenseless. In most situations, they can use magic to defend themselves against a large number of opponents but still come out relatively unscathed.
Yet, a large number of Aes Sedai employ protectors(usually one or more men) who are trained with the sword and also act to defend them in times of danger.
What is a Warder?
A Warder (known as Gaidin [/ˈgaɪ.din/]in the Old Tongue) is a person, traditionally male, who is bonded by an Aes Sedai through the use of saidar to become her bodyguard and protector
The bond has distinct benefits for both parties. The Warder gains greater stamina and physical prowess, a greater capacity to resist evil, the ability to sense shadowspawn at a distance, and greater resistance to injury (I believe their state can be compared similarly to that of a Witcher without also being able to use magic).
The Aes Sedai, for her part, gains a bodyguard, confidant, and ally-in-schemes who is intrinsically linked to her and can be compelled, to a certain extent, through the bond. Both parties can sense the other's general location, physical well-being, and, to some extent, emotional state.
When an Aes Sedai dies, her Warder rarely survives. He completely loses the will to live and will almost always die attempting to avenge his Aes Sedai. A Warder's death is nearly as terrible for his Aes Sedai, creating so much emotional turmoil for her that the Aes Sedai may never again bond another warder.
Also, the Aes Sedai have a status/position to maintain and usually, warders serve in place of servants to help with menial tasks and also tell lies as needed. Unlike the Aes Sedai, warders can lie freely and this ability is frequently used by the Aes Sedai.
In conclusion, the relationship between Aes Sedai and warders ranges from best-of-friends to confidants, to master and servant, or even to marriage. So, the one overarching factor is the existence of the bond between the warder and the Aes Sedai; anything else now depends on the particular people bound by that bond.
P.S Lan and Moiraine are strictly confidants with both having their own distinct goals which may or may not align. They both have long and complex stories which we will write articles on when the series deem it fit to reveal them.
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