Most Aggressive Systems

Of all the system openings out there for white, i.e. London System, KIA, Colle, etc.  What is the most attack oriented? Thank you!

I dont want to learn theory, but I also dont want to play dull games

Try the catalan....

No because 

1. The Catalan isn’t a system as it has a specific move order and doesn’t exist in many cases, such as when black goes 2.g6

2. Even if it were a system, the Catalan is not aggressive at all; White generally wins by gaining a slight positional edge through strong strategic play and then converting accurately.

To the OP: I’d go London or KIA

I am dabbling with the KIA recently. I really like it so far.   Thanks for the feedback

The London is very very good for getting an aggressive game. Same with trompowsky

Much appreciated.  I always get inspired to play the london after i see eric rosen crush kids with it

Just be careful against the c5 and bf5 responses, those can be tricky.

The London is not an aggressive opening.

About the most aggressive system line is the Trompowsky (1.d4 Nf6 2.Bg5).  Only problem is that it is crap against 1...d5.

Against 1...d5, the only good answer really is the Queen's Gambit.  It still limits the theory you need to know.

QGD

SLAV

QGA

SEMI-SLAV

TROMPOWSKY

DUTCH

FRENCH (1.d4 e6 2.e4 - Trompowsky is impossible, avoids the highly complicated English Defense and Nimzo-Indian Defense)

MODERN (1.d4 g6)

That's it!  You avoid the following:

Kings Indian

Grunfeld

Nimzo/Queens Indian

Benoni

Benko

Colle is really nice

hmm I'm not sure if the tromp is crap against d5 if you know how to play it...

as far as I know 1.d4...d5 2.Bg5 is a very decent line

Black get at minimum equality and even a slight edge with perfect play after 1.d4 d5 2.Bg5 f6! (R. Pert - Playing the Trompowski)

You are looking for a unicorn.  System openings do not fight for an initiative out of the opening.  That is what you give up by just trying to develop your pieces to semi-active squares with hopes of outplaying your opponent in the middlegame.  If you want to attack out of the opening, you would need to stick to sharp mainlines (which will require learning a lot of theory).

The OP wants a “system”, and e4 is theoretical and cannot be a “system”

I can play the KIA after 1. e4 though, correct?

The point you make is certainly correct, as I consider employing  the KIA as my main weapon I just want to confirm 1. e4 is fine

Please take a look at this: Reported!

After 1. e4 :

The KIA doesn't have much bite against 1. e4 e5. Nor against the Caro-Kann (although I've played it against that opening). And it's pretty well impossible to play a KIA against the Scandinavian.

Against other moves, it's OK.

1.e4 e5 2.f4

By the way if you want to be aggressive, simply don't play d4. Unlessit is followed by d5 2.e4! (but you'll hear tons of criticism in the opening forum if you follow this route )