Betsy

Your welcome.

watcher, screeching, vampiric, horned, battering or reflex sliver could all potentially be taken out for frenetic sliver or asceticism also I dont see much point in cards such as wings of velis vel being of much help to you...

no run cabal therapy rather than thoughtseize and dont worry about mental misstep, its banned =-)

two things I would change about this deck,

firstly I find with decks like this as soon as you look like a threat (which is generally pretty early on because a lot of players are scared of slivers for some reason) you are likely to face a field wipe or two. For this reason I would consider running cards such as frenetic sliver and creeping renaissance, also you might consider asceticism as a potentially helpful card.

secondly you need to work on your land-base for your general, there are plenty of cheap (I assume your on a budget) any colour lands you could run to get your general out more efficiently, ancient ziggurat, grand coliseum, mirrodin's core shimmering grotto etc...

I love slivers =-)

you cant run phyrexian metamorph in a non-blue EDH because of the blue phyrexian mana, I wish you could though it would go brilliant in my glissa EDH =D

You should run dream halls, discard a card and say hello to your general... or any other of those tasty beasts =-)

I would drop 4 of the walkers for 4 summoner's pacts, also I'd consider dropping some of the other 0 cmc creatures for kobolds as they are moxable. Just an idea.

I would swap out the 2nd slithermuse for a zero mana creature of some description (not an arbor) for summoner's pact and culling the weak if you have already played your bayou, an unlikely combination but even so it gives you an extra card to pact into and if you go for a kobold it can also be used for chrome mox which increases your chance of having the mana necessary to combo off.

Expedition map > wayfarer's bauble. Would you prefer searching for a BASIC land or ANY land? pretty simple choice for me...

Drop some of the more useless creatures for artifact support. Cards such as caged sun, coat of arms and citanul flute are amazing in a mono-colour creature based deck. Also run creatures such as fiend hunter that are capable of taking out threats. And some protection for your general wouldnt go amiss, I find people arent happy to have all creatures at -2/-2

damn thats nasty! =-) I think I like storm

Whats the trow and witness for?

http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&subtype=+[%22Locus%22]

Any card with locus as a subtype =-)

hellbent and threshold work when the spell resolves not when its cast correct?

Commented.

interesting build, I personally dislike poison in EDH so I can't really say that I like the deck but it isnt bad.

You have a lot of cards here that could be improved on, in EDH cards should either give versatility or net you card advantage, a 1-for-1 swap like inquisition or duress while useful against a single opponent are not particularly useful in EDH which is usually played against multiple opponents. Instead I recommend cards like promise of power, phyrexian arena and graveborn muse which I have found amazing in my glissa deck. For removal consider more cards like hex (which gets rid of 6 for the price of 1) or executioners capsule which you can bounce back to your hand instantly when you kill something because of glissa. Equipment such as viridian longbow and thornbite staff are also must haves in a glissa deck as they make excellent use of all of her abilities.

Sorry for the long post.
Betsy.

p.s. You should change the format to EDH, highlander is slightly different :-P

4 cloudposts, 4 glimmerposts and 4 vesuva > urza's mine, plant and tower...

I'm reasonably sure the X's in the genesis DO have to be the same number.

I dont understand cards such as silvos, forgotten ancient and spearbreaker, they dont suit the theme of elf overrun, the same applies to helix ( with ezuri as your general you dont need another high mana requirement win con, pinnacle is too limited in use to be an effective card.) Also if you are doing to run the umbral mantle + mana elf combo you should run sword of the paruns as it doubles the chance of you getting the combo. Artifact support such as caged sun is also very effective in a mono colour edh.
Your deck is good but could do with a lot of refinement, cards such as thornweald and drove of elves arent (from my experience) very good in EDH as they do not provide card advantage or versatility as they are too focused in function, the same applies to pinnacle...
If you need inspiration you could check my ezuri EDH however I have not updated it in a while so it is missing several important cards.

p.s. you should put your general in your sideboard to stop people having to search through you deck to find it, this also avoids confusion about who your general is.

How would gelatinous genesis produce 7 1/1's? if that is all you cast on the 4th turn (assuming you played a land every turn) then you would have 9 mana for it and with 2 doubling seasons in play it would produce 16 4/4's... also where do you get 42 creatures from? I don't understand your maths.

I love this deck but i really dont understand the purpose of the ravagers, what do you use them for?