Amnis
The blue dot thing doesn't grant the blocker ability. The card's text does. The blue dot thing is just a visual indicator for certain blocker creatures. But, for all intents and purposes, it's the cards text that makes it a creature a blocker.

For some reason Amnis doesn't have the symbol. At this point, CS isn't exactly clear about why the creature doesn't have the symbol but they have the word from R&D that it's a blocker creature. Heard two reasons why the symbol isn't there: 1. it's because the creature is specialized blocker and 2. because it was accidently left off. I think the lack of clarity has to do with the fact that the reason has not been specified for Customer Service. They're getting back to me on that after asking R&D.

I'm just tossing out this idea: If you take reason #1, which makes more sense than "was accidently left off," then you could deduce that all-around blockers, ones that can block any non-unblockable creature--regardless if they can or can't attack players or creatures--are the ones that will have the symbol. That way you visually know that the blocker can block anything that can be blocked. The blockers without that symbol you'd be prone to read its text closely to make sure that it can block a certain civ or creature.

Just read Amnis' card text. It calls it a "Darkness Blocker" and then says it taps to block Darkness creatures. Dia Nork's text calles it a "Blocker" but it can tap to blocker any creature. The only difference between the two save that symbol is that one has Darkness in front of the word Blocker. Amnis blocks other creatures by definition of its card text. It's a blocker that just happens to only be able to block certain creatures. To that end, any effects that are subject to blocker creatures like Critical Blade can and do target Amnis. I wish they just stuck the darn symbol on the thing since people feel the symbol grants blocker ability. The symbol doesn't, but it'd make things easier for people to see.

So Crystal Paladin and Larba Geer's effect does also apply to Amnis?

Also on an unrelated issue, base on your experience with CS, if CS confirms with R&D then does it mean that it's set in stone or they can still change their mind down the road?

Thanks.

So, when Sieg grants all their light creatures blocker, how long do the people that think it's the dot that matters spend drawing them on?

HAHA i totally agree, maybe they should include little blocker icon stickers with the next set of cards so we can dynamically put them on as appropriate :p

Yes, any and all effects that can target blocker creatures can target Amnis. It's a blocker creature.

If CS confirms with R&D then that means it's the rule the game designers have settled on aka official. But, things being as they are in the ever-changing word of TCGs, rules can change--especially if something down the line brings up another unexpcted issue. So, it's best to check the official FAQ, if it ever stays abreast of the current card cool.

Well I got my hands on Giliam this past weekend and guess what they included on him....... the Blue Dot so maybe the Blue Dot was left off Amnis by mistake, so Giliam & Amnis are for sure Blockers and all effects that target Blockers target them !!!

I think that Wizards was planning on not putting the blue dot on Giliam, but when they saw all the trouble and talk Amnis made, they decided to put the blue dot on Giliam. Its good that Wizards keeps up with whats happening and trys to avoid problems.

Yeah, the blue dot/black square adds more visually. Gotta have the dot/black square.