Leader

The Leader is a night role from One Night Ultimate Alien

Abilities
The Leader wakes up and sees the Aliens, he also sees which aliens are Zerb and Groob.

The Leader's win condition depends on whether or not Zerb and Groob are both in the game If all Aliens vote for the leader, the Villagers lose, even if they manage to kill an alien. (Note that the Synthetic Alien does not need to vote for the Leader for this to happen)
 * If neither, or only one of them are in play, The leader wins with the village team
 * If both Zerb and Groob are in play, the Leader wins if they both remain alive

Strategy
The strategy for the leader is vastly different depending on whether or not Zerb and Groob are in play

Without Zerb and Groob
When Zerb and Groob is not in play, you have to keep the fact that you're the leader secret,
 * If an Alien is next to you, you can pretend to be the Mortician. Put your neighbor Alien on the spot, and force them to come up with a cover with less information.
 * Remember the difference between pretending to be and claiming to be a Mortician. A good Mortician would not reveal themselves early, as that damages your credibility.
 * Saying that you're the Mortician at all is risky if your other neighbor is the true Mortician, as they can out you and side with the Aliens.
 * You can contest an Alien's claim by saying you were that role. This is risky, as you can't afford splitting the vote between yourself and an Alien like other Village roles can.
 * You can lie to clear the name of a player you know to be on the Village team.
 * You can claim to have viewed an Alien's card. Be careful with this if the Synthetic Alien is in the game, since you can't distingush them from real Aliens, so you might give your team incorrect information.

With Zerb and Groob
When Zerb and Groob are in play, you do not have to worry about all Aliens voting for you if you're revealed as the Leader, since you're no longer on the Village team (and Zerb and Groob are unlikely to vote for you.)
 * Any strategy by the Leader or Zerb/Groob where a player outs themselves can be counter claimed by the other part, taking what was a sure loss and leaving it up to the whims of the table
 * You have to use some of your comparative advantages over them.
 * Zerb and Groob doesn't know who you are.
 * You can lynch a larger number of potential players
 * You don't care if you die (so you can call for a split vote, which Zerb and Groob can not)
 * The regular Alien can be convinced to vote for you
 * You can use the general strategy of a Tanner/Synthetic Alien with the advantage that if a regular Alien figures you out, they're still inclined to vote for you.
 * You can throw suspicion on one of the other Aliens.
 * You can still win if the Synthetic Alien dies

Role Selection
The leader works best in games with more players, 5+ is recommended.

In games without Zerb and Groob, he helps the village team a lot, but also incentivices them to say less, to give the leader room to hide.

When Zerb and Groob are involved, the village can't trust the Leader as much, since he behaves closer to a Blob or Tanner. Adding a regular Alien or two, incentivizes the village to listen to the Leader more

Including roles that switch cards makes it possible for the leader to reveal who the Aliens were, if the switchers are careful not to say where the leader went.

Consider adding roles that the leader can claim to have seen the Aliens with. A true claim from one of these roles might throw the Aliens off the Leader's trail