What do you mean specifically? There's a lot to cover. I can try, though. Sonny is a turn-based strategy rpg. for people who like strategy, turn-based games, rpgs, or in-depth storylines, this game is one of the best. Also, the game has three unique classes with several diverse builds each, several difficulty levels, an abundance of collectible items, and a difficult-to-earn set of achievements. In other words, practically unlimited replay value. The story has just enough mystery and action to keep you motivated as you fight soldiers, zombies, bosses, and even joke enemies. Each fight requires a specific strategy, which adds challenge and variety into the gameplay. To summarize, the game is one of the most well thought out flash games out there.
I, for one, have fallen in love with the turn-based genre with the first games on the C-64, Stars like Dust, Mafia, Kaiser, Vermeer. The strategy aspect there was always the finest. No rushing. Analyzing the situation, watching your enemy, learning which moves are the best, adapt yourself.
Sonny 2, zarco already named many points. There are different classes, so you can choose which fits to your way of playing. Or can try to find out which class could be the best to get ahead. There are a lot of items to loot, you're steadily upgrading.
You start with a party member, that supports you in your fight, heals you, strengthens you, you get another ally that joins, they both level up with you, can be equipped with items.
There's also quite a bit humour here and there. The cut scenes are nicely done for a flash game.
You have a skill tree, which is also able to be changed in the path of the game, for an amount of money, so you can change your skills to better fit the situation, or just change it, because you're higher level, or you found out what's useful for you, and what's not.
You don't get penalties for dying, you can always repeat some other battles to strengthen yourself, or earn that little extra money, for a stronger weapon.