How do we make a healthy assassin? An analogy and some thoughts
Scenario 1: You wake up in the middle of the night suddenly to find a knife stuck in your chest. You look and see a dark figure walk off as you die.
Scenario 2: You wake up in the middle of the night suddenly and hear someone creeping about. You see a dark figure and the glistening of a knife in the moonlight and you quickly grab hold of his arm and fight for your life.
The assassin in both scenarios exploited a vulnerability in your position. Instead of getting you out in broad daylight, he went after you in your sleep. In Scenario 1, you die to him without ever knowing he was there to begin with. In Scenario 2, your fate is decided by how well you can hold off the assassination attempt, despite being in a vulnerable position.
The assassin role is much more than simply killing/deleting someone to eliminate them from the fight. It is about the interaction between the assassin and his target. Assassins should open up (positive) interactions between themselves and the target.
Let's take a look at an assassin that promotes positive interactions: 
When Zed decides to assassinate a target, it is telegraphed. It declares, "Zed will kill this target." There is a delay when he initiates the Death Mark and another delay before the Death Mark procs. This is like Scenario 2 mentioned above: there is time when you realize the assassination is happening and the moment(s) where you are able to react from your vulnerable position. There is ample opportunity to mitigate damage done by the assassin.
Take note that I am emphasizing that Zed promotes player interaction, and I am not commenting on the state of his current strength (the same applies any other examples I might give, unless otherwise specified).
Now let's take a look at an assassin that doesn't promote positive interactions: 
When LeBlanc decides to assassinate a target, it is not distinctly telegraphed. If you are in range for a combo, it is possible that you will be the target of that combo. Thus, your options to not get assassinated is to not be in range for her combo. There is no delay between when she decides to initiate the assassination and the time which the assassination is carried through. It is much more like Scenario 1 where you die from a vulnerable position without warning.
The important thing to note is that Zed has a telegraphed/delayed assassination versus a non-telegraphed/immediate assassination. It is also important to note that both fit the assassin fantasy/theme. Both pick out a target to kill and make it their job to do so.
The issue of non-telegraphed/immediate assassination is exacerbated by mixing mobility with damage.
For example, champions like
have much of their damage associated with their mobility spells. With these examples, their burst is tied to dashing/blinking to the target directly. There is no way to counteract this damage, and so does not promote positive interactions.
This is done to a lesser extent by champions with assassination potential like
who deal damage to you simply by jumping on top of you.
On the other hand, we have assassins whose mobility is not totally innately tied with damage:
. Their mobility is generally used for gaining advantageous positioning and their damage, for the most part, is relegated to their other abilities.
So how do we make a healthy assassin?
First - we allow room for counterplay by telegraphing moves in an indirect fashion. The target should be able to predict moves, but the assassin should have options, especially for positioning. Non-telegraphed/immediate assassinations aren't fun to play against.
Second - we use their innate mobility as a utility for reaching advantageous positioning rather than straight damage output. Against this ties with immediate assassinations.
Those are some of my thoughts. Thanks for reading and let me know what you think - how do we go about making "healthy" assassins for the game?
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