questions about the end-game

[Noeh23]

1) z-reactor seems useless - example: EXL reactor is at nearly 8e04 level. Currect effect LPM is at 164.24...% and KPM is at 323.74...%
Capacity level I just jumped from 105 to 110, filled up the efficiency to 100% and the numbers basically did not move a bit. Like growing the reactor level by +1 gives me more than adding 5 levels of capacity. Did I hit some ceiling? Seems weird.

2) I am still confused about how k is calculated and how it works in the r formula
I am at k = 1e18 and k% 3e17 and when I farm k on Alphabetician then farming k seems to slowly slowly but steadily but k% (farming uncommon) just does not move anymore.
and then how k actually contributes to delta r is still a mystery to me especially during straight line challenge.
Let's say right now my k in the delta r calculation box is 1.74e107^2.91169 .... i am no mahematician but this should be 1.74 x 10^107^2.9... so somewhere around 1.74e310 purely for the value of k
so how us my delta r around 1.1e146 if the k should just be a purely added constant?
i am really ashamed to ask :-) getting so far in the game not having clue how this works :-)

3) any hints on what I should do to increase my EXP gain? I have all the upgrades and my EXP total now is somewhere around 2e24 - the new upgrades in battle spiral are e30. is this only about furthering exp gain via designs and equation and then just wait until my attack speed slowly creeps up? just seems like a lot of waiting and a huge gap from when last time EXP was used for anything.

[Mordtziel]

For the first one, you can see the formulas for the reactors. The EX series reactors have formulas that will approach a specific number but never quite reach it. You're not improving their capacity to improve this investment number, but rather to speed up the rate at which their passive level gain effect improves which doesn't have the same limitations.

As for the second one, your k on the main spiral screen already displays the value of k you have with the exponent. It's very counter-intuitive. So you're not raising e107 to the exponent of 2.91169, but rather, that exponent of 2.91169 got your k to e107. Turning on the challenge itself grants a small boost to your k as well which is affected by that exponent so you'll see it jump a bit higher than it normally would in the challenge (assuming you had the same other upgrades).

And for the last one, generally just attack speed dumping. The faster your kill, the faster you earn rewards. A trick you can do if you're truly desperate is to clear the 20 rewards prior to the best exp tile you can clear using no nuke. Then massively jump up your scavenge setting to massively boost the exp reward tile. Don't forget that there are designs specifically for boosting exp reward as well. Equation too, if you've forgotten about it. In general though, anything m-crit related shouldn't be expected to really have at this point (and doesn't really make a difference in the grand scheme of things at this point). And honestly, the only really nice rewards are the ones from the new attack speed reward upgrade and downwards. Everything above that is too expensive and matters too little.