diff --git a/src/Abilities.cpp b/src/Abilities.cpp
index cc2900e..cc99c10 100644
--- a/src/Abilities.cpp
+++ b/src/Abilities.cpp
@@ -93,19 +93,28 @@ static SkillResult handleSkillBuff(SkillData* skill, int power, ICombatant* sour
     int duration = skill->durationTime[power];
     int strength = skill->values[0][power];
     BuffStack passiveBuff = {
-        skill->drainType == SkillDrainType::PASSIVE ? 1 : duration, // ticks
+        skill->drainType == SkillDrainType::PASSIVE ? 1 : (duration * 100) / MS_PER_COMBAT_TICK, // ticks
         strength, // value
         source->getRef(), // source
         source == target ? BuffClass::NANO : BuffClass::GROUP_NANO, // buff class
     };
 
     int timeBuffId = Abilities::getCSTBFromST(skill->skillType);
+    SkillDrainType drainType = skill->drainType;
     if(!target->addBuff(timeBuffId,
-        [](EntityRef self, Buff* buff, int status, BuffStack* stack) {
+        [drainType](EntityRef self, Buff* buff, int status, BuffStack* stack) {
+            if(buff->id == ECSB_BOUNDINGBALL) {
+                // drain
+                ICombatant* combatant = dynamic_cast<ICombatant*>(self.getEntity());
+                combatant->takeDamage(buff->getLastSource(), 0); // aggro
+            }
             Buffs::timeBuffUpdate(self, buff, status, stack);
+            if(drainType == SkillDrainType::ACTIVE && status == ETBU_DEL)
+                Buffs::timeBuffTimeout(self);
         },
         [](EntityRef self, Buff* buff, time_t currTime) {
-            // no-op
+            if(buff->id == ECSB_BOUNDINGBALL)
+                Buffs::tickDrain(self, buff); // drain
         },
         &passiveBuff)) return SkillResult(); // no result if already buffed
 
diff --git a/src/Buffs.cpp b/src/Buffs.cpp
index c5fd82a..d407fac 100644
--- a/src/Buffs.cpp
+++ b/src/Buffs.cpp
@@ -95,6 +95,12 @@ int Buff::getValue(BuffValueSelector selector) {
     return value;
 }
 
+EntityRef Buff::getLastSource() {
+    if(stacks.empty())
+        return self;
+    return stacks.back().source;
+}
+
 bool Buff::isStale() {
     return stacks.empty();
 }
@@ -142,6 +148,7 @@ void Buffs::timeBuffTick(EntityRef self, Buff* buff) {
         return; // not implemented
     Entity* entity = self.getEntity();
     ICombatant* combatant = dynamic_cast<ICombatant*>(entity);
+
     INITSTRUCT(sP_FE2CL_CHAR_TIME_BUFF_TIME_TICK, pkt);
     pkt.eCT = combatant->getCharType();
     pkt.iID = combatant->getID();
@@ -161,4 +168,30 @@ void Buffs::timeBuffTimeout(EntityRef self) {
     pkt.iConditionBitFlag = combatant->getCompositeCondition();
     NPCManager::sendToViewable(entity, &pkt, P_FE2CL_CHAR_TIME_BUFF_TIME_OUT, sizeof(sP_FE2CL_CHAR_TIME_BUFF_TIME_OUT));
 }
+
+void Buffs::tickDrain(EntityRef self, Buff* buff) {
+    if(self.kind != EntityKind::COMBAT_NPC && self.kind != EntityKind::MOB)
+        return; // not implemented
+    Entity* entity = self.getEntity();
+    ICombatant* combatant = dynamic_cast<ICombatant*>(entity);
+    int damage = combatant->takeDamage(buff->getLastSource(), combatant->getMaxHP() / 100);
+
+    size_t resplen = sizeof(sP_FE2CL_CHAR_TIME_BUFF_TIME_TICK) + sizeof(sSkillResult_Damage);
+    assert(resplen < CN_PACKET_BUFFER_SIZE - 8);
+    uint8_t respbuf[CN_PACKET_BUFFER_SIZE];
+    memset(respbuf, 0, resplen);
+
+    sP_FE2CL_CHAR_TIME_BUFF_TIME_TICK *pkt = (sP_FE2CL_CHAR_TIME_BUFF_TIME_TICK*)respbuf;
+    pkt->iID = self.id;
+    pkt->eCT = combatant->getCharType();
+    pkt->iTB_ID = ECSB_BOUNDINGBALL;
+
+    sSkillResult_Damage *drain = (sSkillResult_Damage*)(respbuf + sizeof(sP_FE2CL_CHAR_TIME_BUFF_TIME_TICK));
+    drain->iDamage = damage;
+    drain->iHP = combatant->getCurrentHP();
+    drain->eCT = pkt->eCT;
+    drain->iID = pkt->iID;
+
+    NPCManager::sendToViewable(self.getEntity(), (void*)&respbuf, P_FE2CL_CHAR_TIME_BUFF_TIME_TICK, resplen);
+}
 #pragma endregion
diff --git a/src/Buffs.hpp b/src/Buffs.hpp
index 95718af..8f395e1 100644
--- a/src/Buffs.hpp
+++ b/src/Buffs.hpp
@@ -66,6 +66,7 @@ public:
     BuffClass maxClass();
 
     int getValue(BuffValueSelector selector);
+    EntityRef getLastSource();
 
     /* 
      * In general, a Buff object won't exist
@@ -88,4 +89,5 @@ namespace Buffs {
     void timeBuffUpdate(EntityRef self, Buff* buff, int status, BuffStack* stack);
     void timeBuffTick(EntityRef self, Buff* buff);
     void timeBuffTimeout(EntityRef self);
+    void tickDrain(EntityRef self, Buff* buff);
 }
diff --git a/src/MobAI.cpp b/src/MobAI.cpp
index 70a8d8e..bcd6a85 100644
--- a/src/MobAI.cpp
+++ b/src/MobAI.cpp
@@ -553,17 +553,6 @@ void MobAI::combatStep(CombatNPC* npc, time_t currTime) {
         return;
     }
 
-    // drain TODO abilities
-    if (self->skillStyle < 0 && (self->lastDrainTime == 0 || currTime - self->lastDrainTime >= 1000)
-        && self->hasBuff(ECSB_BOUNDINGBALL)) {
-        drainMobHP(self, self->maxHealth / 20); // lose 5% every second
-        self->lastDrainTime = currTime;
-    }
-
-    // if drain killed the mob, return early
-    if (self->hp <= 0)
-        return;
-
     // tick buffs
     auto it = npc->buffs.begin();
     while(it != npc->buffs.end()) {
@@ -578,6 +567,10 @@ void MobAI::combatStep(CombatNPC* npc, time_t currTime) {
         else it++;
     }
 
+    // if debuffs killed the mob, return early
+    if (self->hp <= 0)
+        return;
+
     // skip attack if stunned or asleep
     if (self->hasBuff(ECSB_STUN) || self->hasBuff(ECSB_MEZ)) {
         self->skillStyle = -1; // in this case we also reset the any outlying abilities the mob might be winding up.