The Lead is, as I said before, a Pokémon that should ideally be picked last on your team. The reason for this is that not all leads will be suitable for all teams.
The purpose of a lead in my opinion is to start battle off to your rhythm. The lead does not necessarily have to be a speedy Pokémon, although a fast lead is always useful. What it does need to have however, is the ability to impose your will from the get go.
A good option for a lead is for it to immediately set up entry hazards, Pokémon such as Azelf, Infernape and even Metagross make for good leads, as they are either fast enough to set up entry hazards such as stealth rocks and spikes (which will damage your opponent for the rest of the game provided they don’t have a rapid spin user) or they are so bulky that they can take the hit with little to no fear.
Should you choose to run a weather team, you’d want a Pokémon that is able to set up the weather immediately, be it via a move or by an ability, such as drought. This is part of why Tyranitar makes for a very good lead, as it has the ability sand stream, which will immediately summon a sand storm, and it also has good bulk to withstand hits while setting up entry hazards that same turn.
However a great choice in my opinion is an Anti-Lead. What is an anti-lead? Well it’s a Pokémon that is used as a lead to counter your opponent’s lead. For example, Azelf is quite a popular lead Pokémon (although not as popular as it was a few years ago) and as a psychic type, it is weak to dark type attacks. So due to the amount you’ll see Azelf, a Pokémon like Weavile can make for a reliable choice as a lead which can KO your opponent’s lead and prevent them from establishing their rhythm in the game.
There are tones of Pokémon that can make for good leads, just make sure that they are right for what you need them to do, as a good lead can easily make or break your game plan.
Next time we’ll talk about the sweeper.