Auras are capable of deflecting all attacks up to a certain threshold, above which the Aura disappears after blocking off one hit from said attack. Some Auras have elemental alignments, where they immediately disappear after getting hit by their weakness regardless of how strong it was. Certain Wind-based attacks and Battle Chips are also capable of automatically removing Auras regardless of their strength.
Aqua Aura (アクアオーラ,Aqua Aura) is the weakest of all auras. It deflects all attacks doing under 10 damage, and is pierced by Elec attacks.
Fire Aura, known as Flame Aura (フレイムオーラ,Flame Aura) in Japan, deflects all attacks doing under 40 damage, and is pierced by Aqua attacks.
Wood Aura (ウッドオーラ,Wood Aura) deflects all attacks doing under 80 damage, and is pierced by Fire attacks.
Elec Aura (エレキオーラ,Elec Aura) deflects all attacks doing under 100 damage, and is pierced by Wood attacks.
Life Aura 1, known as Dream Aura 1 (ドリームオーラ1,Dream Aura 1) in Japan, deflects all attacks doing under 100 damage and has no weaknesses. This is the Life Virus's primary form of defense, which is then picked up by Bass.
Life Aura 2 (Dream Aura 2) deflects all attacks doing under 150 damage and has no weaknesses.
Life Aura 3 (Dream Aura 3) deflects all attacks doing under 200 damage and has no weaknesses. From Mega Man Battle Network 3 onwards, variants of Life Aura are done away with, and Life Aura 3 automatically became the only Life Aura (ドリームオーラ,Life AuraDream Aura) chip. However, it now has a time limit of aproximately 5-6 turns. It also appears in the first Mega Man Star Force game.
Aura (オーラ,Aura) is simple version of Life Aura 1 in the third game, being yellow instead of purple and deflecting attacks doing under 100 damage. It also appears in the Mega Man Star Force series.
Dark Aura (ダークネスオーラ,Dark AuraDarkness Aura) is a strengthened version of Life Aura, deflecting attacks doing under 300 damage. It is a Dark Chip, requiring a dark hole in the field or the Dark License program to be used.