Torpor Orb reads: 'Creatures entering the battlefield don't cause abilities to trigger.' This is a continuous static ability that applies only going forward from the moment Torpor Orb is on the battlefield. It does not retroactively suppress or remove any triggered abilities from permanents already in play (CR 611.3).
Importantly, Torpor Orb itself entering the battlefield does not suppress its own entry trigger — but Torpor Orb has no 'enters the battlefield' triggered ability itself, so that is moot. What matters is that it cannot reach back in time to stop triggers that already fired from permanents that entered before it (CR 603.6).
Additionally, Torpor Orb only suppresses triggered abilities that trigger off creatures entering the battlefield. Static abilities, activated abilities, and triggered abilities that trigger for other reasons (like attacking, dying, or upkeep) are completely unaffected, even for creatures entering after Torpor Orb (CR 603.1).
Concrete example: You control a Restoration Angel that entered before your opponent plays Torpor Orb. Restoration Angel's 'enters the battlefield' trigger already resolved (or missed its window) before Torpor Orb arrived — Torpor Orb does nothing to Restoration Angel. However, if you later blink Restoration Angel with another effect while Torpor Orb is on the battlefield, Restoration Angel's ETB trigger is suppressed upon that re-entry.
Unofficial fan resource — not affiliated with or endorsed by Wizards of the Coast. Answers are AI-generated estimates grounded in the Comprehensive Rules and are not a substitute for an official judge. Verify anything match-critical.