I’ve been putting together the next “one shot” in and episodic dnd campaign. One of the things I’ve tried to include is a complex trap, as I’m not familiar with them, and want to have some experience.
There are 5 characters at level 12, and there will be a few fights, to whittle them down a little bit, probably a short rest before final fight. 
I’ve designed a machine protector, made by Primus and corrupted by this organization. The way to beat it is to destroy the energy core (300 hp) behind a barrier of temp hp (50 max). The traps abilities are:

initiative 20: give energy core 25 hp to max of 50

Initiative 15: 2 earth tremor spells cast at 3rd level (3d6 and prone on fail) hitting closest characters (DC 17)

Initiative 10: lighting ray (call lighting spell at 5 level) Dex save (dc 17) targets closest creature to energy core

Initiative count 1: summon 1d4+1 bulzeau within 5ft of machine.

If the energy core drops below 150 hp, the shield goes off at initiative 10 as well, a second earth tremor spell happens at same time, lightning targets 2 people, and summoning bulzeau happens again on initiative 15

Idk how well this transfers to a legitimate fight. Please if you have feedback or have ran any complex traps, give me some tips, or suggestions. Thanks for reading all the way through, ik this is long!

I also added if dispel magic is cast targeting the part of the trap casting it, it either lowers the level of the spell, decreases the temp hp given, or subtracts some of the bulzeaus summoned. 

This sounds cool, I think it may drag on a bit since the actions are essentially the same throughout the fight. You can solve this by adding in additional enemies that can last longer than the bulzea. Maybe some large mechanical construct(s) that some players will have to engage while others target the core. It sounds like a cool concept though.

if its made by primus, why does it summon feinds?

maybe, like, a lot of pentadrones?

They said it got corrupted in the top post. So it got modified to summon fiends instead of modrons.

Quote from KyrneGnomeBarbarian >>

They said it got corrupted in the top post. So it got modified to summon fiends instead of modrons.

 man, the things primus makes need to stop getting corrupted

Think of them as files with bad antivirus software.