Ali From Cairo was once restricted in Type 1 for being too powerful, but in 93/94 we can play four of them so of course we should! The thing that makes Ali so powerful is that you essentially become unkillable if he is in play. The problem is that Ali more often than not becomes the target of a Swords to Plowshares, Terror, Lightning Bolt or something similar. And as soon as that happens you are no longer invincible.
This deck is built around solving exactly that problem, so Ali can stick around and make you impossible to kill for the rest of the game. One of most common ways of doing this is by enchanting Ali with cards like Spectral Cloak or Anti-Magic Aura to protect him from spot removal. Another often used way to keep Ali alive is to use Jade Monolith to protect Ali from damage. Because as long as Ali is alive you can redirect any amount of damage to yourself.
As most combo decks Cloaked Ali usually have some number of counterspells in the deck to protect the combo. After the combo is assembled there are still threats like Balance, Chaos Orb (in case of Anti-Magic Aura) and Wrath of God and that’s why Counterspells could be a good addition.
That’s the combo part which this deck is built around but of course you need other cards, for example it’s always good to have a wincon. Most known versions use Serendib Efreet and some burn spells which essentially gives the deck two strategies. It can either win as a UR Control deck or assemble the combo. The version you see above takes a completely different route and use Energy Flux and Blood Moon to make it more of a prison deck. Another part of that strategy is to “overload” your opponents Disenchants so the Anti-Magic Aura can stick around.
Other cards that are good with Ali are of course cards that do damage to you, as you can’t take more damage when you’re at 1 life. One popular choice is Orcish Artillery which also serves as a wincon. If you go into green you can also play Ifh-Biff Efreet, as it doesn’t kill Ali and with Ali in play it doesn’t kill you.