Baern Snagglehorn:
Ideally ending movement out of direct sight of the yuan-ti.
Baern raises a good point here. The cluttered engine room should be an asset for those of you trying to advance on the firbolg without exposing yourselves to his partner. While in the engine room, anyone can use a
bonus action to do one of the following:
1. Dexterity (Stealth) check. This will be contested by yuan-ti's Perception. If you succeed, he'll know your general vicinity but not your exact location. So you'll still be susceptible to Area of Effect spells/weapons but he won't be able to target you without anything that requires seeing you.
2. Wisdom (Survival) check. With a 10 or better, you gain the benefit of partial cover. With a 20 or better, you can gain the benefit of full cover.