BG Elfos Tyvar (EDH / Commander)

Lathril, Blade of the Elves leads a tuned re-think of the Elven Empire pre-con, without going all-in financially. Playtesting finds this deck a potent tribal aggro force, regardless of if Lathril's activated ability condition is met. Thus, there is no rush to get her to the field unless you're approaching 10 elves or have opportunities to benefit from her triggered ability or get her through on-board - the direct approach does not require her constant oversight. However her ability can be doubled up as a potent win-con with the help of a timely Vitalize.

Getting Lathril through for damage:

Familiar Ground - Your creatures can't be double blocked and Lathril has menace.
Elderfang Venom - Deathtouch to your attackers.
Bow of Nylea - Deathtouch to your attackers.
Trailblazer's Boots - nonbasic landwalk
Rogue's Passage

Notable ramp & ramp strategies:

Circle of Dreams Druid - taps for a green mana for each creature you control
Elvish Archdruid - taps for a green mana for each elf you control
Priest of Titania - taps for a green mana for each elf on the battlefield
Marwyn, the Nurturer - taps for green equal to power
Canopy Tactician - taps for 3 green mana
Tyvar Kell - grants all elves 'tap for one black mana'

Elf token (ET) generation and tools:

Prowess of the Fair - replaces your dying non-token elves with an ET
Elven Ambush - instant which creates an ET for each elf you control
Return Upon the Tide - return elf from graveyard, get two ETs
Tyvar Kell - 0 ability creates an ET
Elvish Warmaster - once per turn ET upon another elf entering the battlefield
Eyeblight Cullers - LTB, 3 ETs
Imperious Perfect - green + tap to create an ET
Wolverine Riders - create an ET each upkeep
Nadier, Agent of the Duskenel - LTB, ETs equal to power
Lathril, Blade of the Elves - ETs = to damage dealt to opponent
Skemfar Elderhall - sac for removal plus two ETs
Doubling Season - produce double tokens

Draw & moving through the deck:

Slate of Ancestry - discard hand, draw cards equal to creatures you control.
Pyre of Heroes - trade up to more powerful elves from the library while re-stocking the graveyard for a big recursion spell.
Roots of Wisdom - self-mills 3 returning options to hand or replaces itself
Harald Unites the Elves - self-mills 3 returning an elf or Tyvar to the battlefield
Bounty of Skemfar - look at top 6, play a land, keep an elf.
Beast Whisperer - cast creature, draw card.
Oakhame Adversary - draw a card when damages opponent
Realmwalker - look at and cast chosen creature type from top of library anytime.
Herald's Horn - look at top card in upkeep, if it's chosen creature type, you may place in hand.
Harald, King of Skemfar - ETB look at top 5, reveal elf, warrior or Tyvar and put in hand.
Cream of the Crop - scry-like ability for each creature you bring into play.

Toolbox:

Vitalize - untap all creatures you control, best used after Lathril uses her ability.
Allosaurus Shepherd - Makes all your green spells uncounterable, late game pump.

Honorable mention, not in the current build:

Miara, Thorn of the Glade - elf death triggers 'may pay 1 life, draw a card'.
Sword of the Animist - equipped creature brings a basic land to the battle field, tapped, upon attack.
Wood Elves - brings a forest onto the battlefield
Earthcraft - tap a creature to untap a basic land.
Llanowar Tribe - taps for 3 green mana