Torpor Orb‘s ability prevents any abilities from triggering when a creatures enters the battlefield. At first look this seems to be pretty basic and straightforward, but there are a few things to be aware of.

First of all, the easy part, when a creature enters the battlefield its enters the battlefield ability will not trigger. These abilities do not trigger at all, they do not trigger and then become countered. This means that you will not choose targets for the ability or anything associated with putting this ability on the stack. So for example, if an Aether Adept were to come into play, its ability will not trigger. Because of Topor Orb, it will be a 2/2 for 1UU.

Creatures entering the battlefield will also not trigger abilities of other permanents. So Suture Priest‘s two abilities cannot trigger at all when Torpor Orb is in play.

Finally, some abilities trigger when a permanent or multiple types of permanents enter play. For example Confusion in the Ranks triggers whenever an artifact, creature or enchantment enters the battlefield. WIth Torpor Orb this ability can still trigger but it will only do so for artifacts and enchantments. Because of the way Torpor Orb works, an artifact creature entering the battlefield will not trigger Confusion in the Ranks ability. It does not matter that it is also an artifact, what matters is that it is a creature and therefore it coming into play will not trigger any abilities.