I want to make a custom Siphon skill that is cast and then works for its duration without channeling. I also want it to stack for the caster, meaning:
Caster uses siphon on enemy A
Enemy A loses 10HP/s + Caster gains 10HP/s
Caster uses siphon on enemy B before the siphon on A ends
Enemies A + B lose 10HP/s each + Caster gains 20HP/s
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Caster uses siphon on enemy C
Enemy A loses 10HP/s + Caster gains 10HP/s
Caster uses siphon again on enemy C before siphon is finished
Siphon duration on enemy C is refreshed but still only siphons 10HP/s
Caster uses siphon on enemy A
Enemy A loses 10HP/s + Caster gains 10HP/s
Caster uses siphon on enemy B before the siphon on A ends
Enemies A + B lose 10HP/s each + Caster gains 20HP/s
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Caster uses siphon on enemy C
Enemy A loses 10HP/s + Caster gains 10HP/s
Caster uses siphon again on enemy C before siphon is finished
Siphon duration on enemy C is refreshed but still only siphons 10HP/s