Every. Single. One.
At a 50% chance of getting 20 ISO from any given node, some napkin math suggests that the odds of getting 6 such results in a row is, rounding, about 2 chances in 100.
Or about what my odds of getting any given 4* are from a Heroic/event token.
Why can’t I “win” that lottery as often with Heroic tokens as I do with node clears? 
It’s one of the main reasons I can’t stand pve. With pvp, you’re constantly winning great prizes every 2-3 battles. With pve, you’re grinding away like crazy for a 2* progression reward, getting 20 iso after each intense, health-pack-draining fight. So not worth it.
I had the same pattern with my last 2 clears in Eots. 20iso on every node. 2 clears in a row.
That is just too weird. And annoying.
I got the exact same thing on my last clear of EotS with the single exception of getting one CP on the last node.
I swear these developers are stupid. This is a problem that any seasoned developer would have fixed in the first year of a game being released. Anything that decreases player motivation should be dealt with. If this is a simple case of probability involving 4 elements from a programming standpoint this should be relatively easy to change. The fact that it’s not at this time shows indifference.
On a side note, why 50%? Why make it so unnecessarily hard to get rewards from a node? That’s just mean spirited, another reason I dislike them.
Yeah my luck has not been any better. 5 clears on EOTS, I have 5 missions that have 4 rewards. Only one of them has given me something besides 20 iso. That’s 20 rewards available and 6 earned.
They need to fix this.
And if we nitpick it and take away the guaranteed reward for first clear. That’s 1 reward out of 15 for me on at 5 clears.
That was me this morning. So 11 straight nodes with a 20 ISO reward before I finally got a non-20 ISO reward! Or a .0005 (rounded) chance. One in 2000, that’s me!
At least it was the CP. 11 straight 20’s followed by a crit boost would have meant murderspree time.
(Dear NSA: that’s called “black humor.”)
I was thinking more about mine. I did 5 clears that’s 20 chances at a reward that’s not the first clear. Then I ground the final node a bit hoping for cp. Did it maybe 4 times.
That’s 24 nodes 1 reward that was not a 20iso. And I have no idea how many health packs I burnt for 260 iso.
We need this changed somehow.
I’ve gotten 20 iso on last 3 clears, every single node, probably due to all of them having that green checkmark though.
20 iso is better than Critical Boost, so think of it that way!