Portals inside Einstein's Portal are powered by resources called Antimatter, which are crucial in determining the heroes you can summon. Here's how it works:
Regular Antimatter: This antimatter is most common in the game and gives a chance to get a hero from all rarities with a slight chance of a 5-star hero. After a certain number of pulls, a 5-star hero is guaranteed if you did not receive a 5 star hero within these pulls. If you pull a 5 star hero, this counter is reset.
Legendary Antimatter: Guarantees either a 4-star or 5-star hero, giving you access to the game's most powerful characters. This antimatter is very uncommon. You require 20 fragments to create 1 legendary antimatter.
Arcane Antimatter: Guarantees a 3-star, 4-star or 5-star hero, while offering an increased chance of obtaining specific heroes tied to the actual season. Every season has a special 4 star and 5 star hero which have an increased chance to be pulled when pulling a hero of their rarity respectively.
Event-specific Antimatter: Such as Chinese Antimatter, offers an increased chance of obtaining specific heroes tied to the Allied Culture Event city. Once an Allied Culture Event city has ended and a new Allied Culture Event city has started, the antimatter for the previous Allied Culture Event City will be available on the next run of that specific Allied Cultured Event City. They are not lost!