Temple Altisaur's ability applies to all Dinosaurs you control other than Temple Altisaur that would be dealt damage, not just one of them (you don't choose which of those it applies to) (C.R. 611.3a, 611.3).
Each time a source (not just a creature [C.R. 119.7]) would deal damage (not just combat damage) to a Dinosaur you control other than Temple Altosaur, all but 1 of that damage is prevented.
EDIT: Correction after comment 7 was posted. I mis-read the card.
EDIT (Jul. 23, 2019): Clarification.
Temple Altisaur's ability applies to all Dinosaurs you control other than Temple Altisaur, not just one of them (you don't choose which of those it applies to) (C.R. 611.3a, 611.3).
Each time a source (not just a creature [C.R. 119.7]) would deal damage (not just combat damage) to a Dinosaur you control other than Temple Altosaur, 1 of that damage is prevented.
Slight correction, Temple Altisaur doesn't prevent 1 damage to each dinosaur. It prevents "all but 1 of that damage" to each other dinosaur. Big difference.
[Strike]Maybe I'm too used to playing yugioh, but it sounds like I only get 1 per time not instance.[/strike]
Oh, you just reworded it slightly. Because of the if trigger it is each instance noteach time.
Temple Altisaur's ability is not a triggered ability (it doesn't include "when", "at", or "whenever") (C.R. 603.1). In any case, under C.R. 611.3a, Temple Altisaur's effect isn't "locked in" to a particular source of damage or to a particular Dinosaur you control (other than Temple Altisaur).
Temple Altisaur's ability is not a triggered ability (it doesn't include "when", "at", or "whenever") (C.R. 603.1). In any case, under C.R. 611.3a, Temple Altisaur's effect isn't "locked in" to a particular source of damage or to a particular Dinosaur you control (other than Temple Altisaur).
If-then statements aren't considered triggers in magic? weird.
Each time a source (not just a creature [C.R. 119.7]) would deal damage (not just combat damage) to a Dinosaur you control other than Temple Altosaur, all but 1 of that damage is prevented.
EDIT: Correction after comment 7 was posted. I mis-read the card.
EDIT (Jul. 23, 2019): Clarification.
Maybe I'm too used to playing yugioh, but it sounds like I only get 1 per time not instance.Oh, you just reworded it slightly. Because of the if trigger it is each instance not each time.
Slight correction, Temple Altisaur doesn't prevent 1 damage to each dinosaur. It prevents "all but 1 of that damage" to each other dinosaur. Big difference.
If-then statements aren't considered triggers in magic? weird.