Nice, this is what I use for my bloodlust banner that drops from fallen enemies.
<actor behavior="composite">
<behavior>
<dictionary>
<entry name="hp"><int>200</int></entry>
<entry name="multiplayer-scale-hp"><bool>true</bool></entry>
<float name="aggro-range">50</float>
<float name="max-range">50</float>
<entry name="ignore-hit-effects"><bool>true</bool></entry>
<vec2 name="hp-bar">0 -1.25</vec2>
<entry name="death-snd"><string>sound/monsters.xml:death_tower_banner</string></entry>
<entry name="hit-effect"><string>effects/particles.xml:hit_eye_1_small</string></entry>
<entry name="hit-particle"><string>effects/particles.xml:particle_eye_1_small</string></entry>
<entry name="corpse"><string>actors/tower_banner_1_razed.xml</string></entry>
<float name="editor-range-marker">5</float>
<dictionary name="movement">
<string name="type">passive</string>
<bool name="set-dir">false</bool>
</dictionary>
<array name="skills">
<dictionary>
<string name="type">buff</string>
<int name="cooldown">100</int>
<float name="range">50</float>
<float name="cast-range">5</float>
<string name="category">Enemy</string>
<string name="buff">buffs/banner_bloodlust.xml</string>
</dictionary>
</array>
</dictionary>
</behavior>
And then the buff:
<buff>
<behavior>
<dictionary>
<string name="color">255 0 0</string>
<int name="duration">150</int>
<float name="dmg-mul">1.5</float>
<float name="speed-mul">1.5</float>
<bool name="snare">false</bool>
<bool name="stun">false</bool>
</dictionary>
</behavior>
</buff>
The most notable difference seems to be that mine don't go on and off when you move away from it. I wanted it to be like a totem that always gives enemies the buff even when you are not close to it. I made a (enemy)healing banner and a manadrain banner.