Plains of Eidolon's bounty stage "defend the area" has some problems.

[ChozenBardoUmbra]

1. The zone is too big to defend, enemies usually spawn too scattered around it and are pretty hard to see at times.

2. The secondary objective is too punishing compared to the other 2 open worlds, it is at 50%, and I feel it drains too fast, coupled with the points above.

 

If I played that bounty stage solo, I certainly need to use my Necramech to destroy the ships to be able to complete the secondary objective, I can't imagine newer players who don't have the damage or a Necramech having a good time with this particular situation, I would suggest reducing the Zone (closer to what Cambion drift counterpart is should be good), improve the spawning or make the drain less punishing.

[(NSW)HedEmpTy]

AH, yeah, this is the "Liberate The Camp" bounty stage, the community has been complaining about it for who knows how long, because it's absolutely notorious for being terrible. You've basically hit everything wrong with it right on target - huge area, scattered and erratic spawns, punishingly fast drain rate, and consequently a really difficult bonus objective (and not it a fun challenge way, but in a needless stress way).

Also, as a mostly-solo player, I agree - you need a Necramech just to get the bonus.

[(PSN)FunyFlyBoy]

You need a Necramech in a group as well. It's very rare for a group to even finish this damned challenge for the same reasons mentioned. Even running around with my high range Saryn, I still find it leagues easier to just pop a Necramech, go into Turret mode, and just lob explosives in all directions versus trying to hunt down some random elusive group of Grineer I cannot find because they could potentially be in the cave system underneath the objective.

That has happened before, were an entire cave network of Grineer we're counting towards the drain of the blood objective above ground. If you're having spawning issues, good chance there is a cave entrance nearby and grineer are outside your 30m radar on the point within that cave.