Does Overwhelming Splendor affect creatures that enter the battlefield after it resolves?

Overwhelming Splendor is an Aura that enchants a player and creates two continuous effects: it removes all abilities from creatures that player controls, and it makes each of those creatures a 1/1 with no abilities. Because these are static abilities generating continuous effects, they apply at all times while the enchantment is on the battlefield — not just at the moment it resolves.

Under CR 611.3, continuous effects that modify characteristics of objects apply to all objects that fit their criteria at any given moment. This means any creature the enchanted player puts onto the battlefield after Overwhelming Splendor has already resolved will immediately fall under its effect as soon as it enters.

This is an important contrast to 'enters the battlefield' triggered abilities, which only fire once. Static effects like Overwhelming Splendor instead continuously re-evaluate which permanents they affect as the game state changes (CR 604.2).

There is one nuance: abilities granted by other Auras or Equipment attached to a creature the enchanted player controls are also stripped, since those abilities are treated as belonging to the creature (CR 702.2). However, the Aura or Equipment itself remains attached — it just doesn't grant its abilities while Overwhelming Splendor is in effect.

Example: Your opponent controls Overwhelming Splendor enchanting you. You cast a Baneslayer Angel. It enters the battlefield as a 1/1 with no abilities — Flying, First Strike, Lifelink, and its other abilities are all immediately removed by Overwhelming Splendor's continuous effect.