<AbilityBonus InternalName="Blood_AltarianAbility">
<AbilityBonusOption InternalName="Blood_Altarian">
<DisplayName>Altarian Blood</DisplayName>
<Description>+10% Experience</Description>
<Icon>RoundCrest_Altar.png</Icon>
<GameModifier>
<ModType>Unit</ModType>
<Attribute>AdjustUnitStat</Attribute>
<StrVal>UnitStat_ExpBonus</StrVal>
<Value>10</Value>
<Provides>+10% Experience</Provides>
</GameModifier>
<HideWhenUpgraded>0</HideWhenUpgraded>
<AIData AIPersonality="AI_General">
<AIPriority>5</AIPriority>
</AIData>
</AbilityBonusOption>
</AbilityBonus>
No difficult stuff there. The problem is when you add a new bloodline you have to add it to the game somehow. What you want to do for this is create a new race with the new bloodline. For that, you must create a new race with all the unittypes to go with it. I have an overview of that process here: https://forums.elementalgame.com/435287/get;3262598
I would strongly recommend that you check out impinc's race editor as it can automate a big part of the process for you: https://forums.elementalgame.com/433305
