You can play blackjack with a level of skill and expect to win with some outstanding numbers depending on your level of skill.
Card counters can gain an edge of 0.6%-1.7% depending on their skill
Shuffle trackers keep track of cards they saw dealt, and follow them through the shuffle to the next shoe, and can further add advantage to their EV. They may keep track of several cards, or as few as only one card. If a player is skilled enough to use the cut card to manipulate an ace to be dealt to them immediately after the shuffle, or predict when an ace is goign to be dealt based on the cards dealt immediately prior to is, their expected return that very hand is 153%!! so that one card can be very valuable. Oporunities like that are very rare and i have only pulled off that stunt once, though i wont tell how.
In the past, you used to be able to "guess" what the dealers hole card was based on some "signs" that could be read from the card itself and the dealer, this is known as hole card play and can be VERY advantageous, though it is gone with history now for the most part.
There is still "luck involved even if you are a card counter or not, even when you hold an edge over the house, its only an edge, and anythign could happen even though winning is slightly more likely at the given moment.
Myself, Professional Blackjack player