Originally Posted by
tescrin
@ozimek While Nestalim hit fringe points for Marsh Casualties; the real reason for it is that it's instant speed for Elves. Being able to wipe their board after they go deep for a hoof or in the middle of trying to Elf-Ball during a Glimpse, you can really munch them. It's also a huge difference between T2 and T3. T2 instant speed lets you be *very* prepared, and it means you can keep laying down 2-mana threats when you get to 4 mana, which again, is much easier compared to 5 mana. Elves is a defensive game a lot of the time, where you are mostly trying to not-lose[*]; since you're more heavily favored the longer the game goes.
[*]Note: This is my experience with other decks and I assume it applies here. My record with the last deck I was maining was 13-0 in matches against elves, and this is how I approached it.
Similarly, Casualties is mildly relevant against TES, where if they go off T1 you can live with Casualties, but are more likely to die with Deluge. Lastly, D&T is also weak to it; in particularly in response to one of their Gimmicks. For instance, let's say you bait a Wisp by Pushing a Thalia or some such; when they Wisp to protect her, you can casualties and still kill both of them [cast when the trigger is on the stack.] It may not be true CA in this case (since you also spent a push), but little edges like that are a big deal.