Well, since you mentioned LeBlanc, I guess this is a better place than a facebook note to write (and ask!) about my perceptions of her passive.
Power of Control
Unlike Shaco, LeBlanc's passive is dependent upon:
- "negative" play: getting hit
- an external source of damage
That is, the LeBlanc user has no control over the passive's invocation.
Potential for Unavoidable Uselessness
The reason I mention Shaco is because the bugs that affect the doppleganger ability can be minimized, or eliminated, by control. The doppleganger ability currently suffers from (what I'd call bugs...) these constraints:
- champion can be pinged; the ping persists and is not replicated across the doppleganger
- champion can be marked graphically somehow, and the mark will not be replicated across the doppleganger
- champion can be affected by a CC, and the doppleganger will not be affected
To avoid a ping, Shaco can get out be out of sight (bushes, etc.) when choosing to invoke the doppleganger ability. The visual effect and CC can be avoided by choosing to invoke the doppleganger ability when the visual effect and CC are no longer afflicting Shaco.
As someone who has played LeBlanc, here is how I have discovered causing guaranteed uselessness of an enemy LeBlanc.
1. Ping them immediately. I have the control of their passive. Combined with the ping, I can identify the real LeBlanc at all times.
2. Notice the graphic on LeBlanc. (example: Oracle's Elixir indicator) It will not be replicated across the doppleganger.
3. Cast a CC on LeBlanc at around 45/50% life. The doppleganger will immediately start auto-attacking while the real LeBlanc remains stunned; the slowed LeBlanc will be slow (with the slow graphic effect) while the doppleganger has no affliction.
Another bug that makes her uncontrolled passive a curse-instead-of-blessing can be replicated below. This is also why I noted "external source of damage" in the Power of Control section instead of NPC versus player sources.
Summary: LeBlanc's passive causes creeps to reset.
1. Go to the golem spawn point with LeBlanc.
2. Start attacking and damaging down the golem until your health reaches the point of invoking LeBlanc's passive.
3. ---> The golem has reset.
If you didn't design LeBlanc's passive, could you ask whoever did to maybe share why it was designed so? The flashy, notable spell effects for all her abilities, combined with a short duration and a completely null attack potential, make me wonder about the principles behind this uncontrollable passive.