Rules clarifications

[Ereshkigal]

i read the manual, but maybe because english it's not my first language, maybe because the manual itself is not that clear or maybe because i have the mindset of wh40k and how things works there... but i didn't grasp some rules. Could you help me a bit?
First thing a warjack with 3 different melee weapons, attacks 3 times without spending any focus? And can make extra attacks using focus right?
Second, i have to declare if i want to do some extra attacks before starting to roll or can i let's say, attack, see if i kill the target and then choose if i want to do an extra attack?
Third, i have to declare the damage boost before rolling to hit or just before rolling the damage? Can i boost an already boosted roll?
Fourth, can i reach melee range without charging? This because warjacks have to spend 1 focus to charge but not to normally move.
Lastly, a model engaged can leave the combat in his activation but it takes a free strike, right?

Thanks in advance.

[CasaHouse]

Yes. A warjack with three weapons can make an initial attack with each one, then you can spend a focus to buy another attack with a weapon of your choosing.

Second: You buy an extra attack after fully resolving the attack beforehand. So yes, you can attack, see if you kill the target, and then make the decision of whether or not you want to buy more attacks.

Third: You declare you're boosting the damage roll AFTER rolling to hit, just before rolling the damage dice. Any given roll can only ever be boosted once. So, for example, you can't boost the damage on your first attack after charging, since the charge already boosts the damage for the first swing.

[Ereshkigal]

I edited for a couple more questions, but thanks for your answers! Your answers made me think... why take troopers instead of solos and several warjacks? It seems the difference in power is really big, but i'm really noob..

[Falkman]

The main reason to take troopers is that they can cover more physical space, don't require resources to run and are cheaper.
But there really are lots of reasons to run troops, some of them hit incredibly hard (weapon masters), some of them are very nimble and hard to hit and so can be in the way of other models, some have special abilities that greatly help other parts of your army and so on.
Warjacks can't really do much without Focus, and since your warcaster only has so much Focus you can't take an infinite amount of warjacks if you want them to run at peak performance.

To answer your fourth and fifth questions, you can reach melee range without charging, just walk or run into it. And you can definitely just walk away from a combat as well, but as you've figured out you then might take free strikes.

[Thanatos_elNyx]

why take troopers instead of solos and several warjacks? It seems the difference in power is really big, but i'm really noob..

Just wait till you see a unit of Sentinels charge something.
9 points for ten dudes that do 12+4D6 damage on the charge.

[Ereshkigal]

I have another stupid question: what's the difference between deathjack necromancy and an arc node? The only thing i found being different is that the deathjack can use his own focus to cast his caster spells and can do it in his activation instead of his master activation. Am i right or are there some nuances i didn't catch?

[Deadnight]

I have another stupid question: what's the difference between deathjack necromancy and an arc node? The only thing i found being different is that the deathjack can use his own focus to cast his caster spells and can do it in his activation instead of his master activation. Am i right or are there some nuances i didn't catch?

pretty much. the deathjack is a warjack that is casting a spell.

With an arc node, its your warcaster (ie in his activation) that casts the spell - the arc node is the point from which the spell comes from. so you activate the jack, move it into position. then you activate the caster, and cast a spell through the jack.

[Jerrus]

Another differance is that when channeling the channeler cannot be engaged in melee.

[BTJ]

Just wait till you see a unit of Sentinels charge something.
9 points for ten dudes that do 12+4D6 damage on the charge.

Or mage hunter strike forces. What's that now, you ignored my iron flesh, 6 focus and the freaking BUILDING?