Can you stack multiple combat damage prevention effects so that a creature takes zero damage total?

Damage prevention effects work by replacing damage events before they occur. When a creature would receive damage, any applicable prevention effects may be applied. If multiple prevention shields or effects exist, they are applied one at a time — each reducing the remaining damage — until either all damage is prevented or all shields are exhausted. This is governed by CR 615 (replacement effects) and CR 616 (interaction of replacement effects).

Each prevention effect only needs to cover part of the incoming damage. For example, if a creature is dealt 5 damage and you have one effect that prevents 2 damage and another that prevents 3 damage, both can apply in sequence, resulting in zero damage being dealt to the creature.

The controller of the affected permanent (or the player, if it's a player) typically chooses the order in which to apply replacement effects that could each apply to the same event (CR 616.1). This means you can stack them optimally to maximize prevention.

Concrete example: Your opponent's 5/5 attacks and you block with your 2/2. You have two separate "prevent the next 2 damage" shields on your 2/2 (e.g., from two activations of a prevention ability). The 5 combat damage is prevented: first shield removes 2 (3 remaining), second shield removes 2 more (1 remaining), but only 4 total is prevented — you'd still take 1. However, if both shields together cover all 5 damage (e.g., a 3-damage shield and a 2-damage shield), your creature takes zero damage and survives.

Note: Some damage cannot be prevented at all — damage from sources with infect can still be prevented normally, but damage marked as unpreventable (e.g., from cards like Skullcrack, CR 615.1d) cannot be reduced by any prevention effect regardless of how many you stack.