This one is very agressive, always attacking :
Softonic has viruses
In my opinion, the best way to use a chess engine is for post game analysis:
If you want to an aggressive or strong chess engine to play... pick any of them. I expect any of these to play over 2500 elo and will likely beat most players. I believe Stockfish can play at 3500.
Some chess engines, like Komodo, have more realistic personalities so you can adjust the skill level and playing style. Komodo is the engine used for Chess.com bots. Rodent is a free chess engine with personalities.
Stefan Pohl has already crunched the numbers for engine aggressiveness. See here:
https://www.sp-cc.de/eas-ratinglist.htm
It's a shame this guy is gone, I could have really set him up with some awesome aggressive engines.
whats the engine?
Prettty much any engine you want to use.