No, you cannot use a Revenant Assassin as a high-damage striker.
Original Assassins have fantastic mobility, interesting secondary effects, and absolutely worthless damage (a thought explored in both practice and theory). Roughly speaking, you'll want your striker's DPR to fall within (8*Level+24)/4 and (8*Level+24)/2.
To calculate DPR, use the following formula:
(1-(BaseDefense+Level-ToHit-1)/20-CritChance)*(WeaponDamageAverage+StaticModifier)+(CritChance)*(CritDamage+StaticModifier+ExtraDamage)
Where:
- Base defense = 14 for AC, or 12 for NADs (Fort, Ref, Will)
- Level is level of the character
- ToHit is the total attack modifers of the character
- Critchance is .05 (20), .1 (19-20) or .15 (18-20)
- CritDamage is the maximized Weapon Die * Number of Dice
- WeaponDamageAverage is Number of Dice * die average * n[W]
- Die Average = sides/2+.5
- Brutal 1 = sides/2+1
- Brutal 2 = Sides/2+1.5
- Static Modifier is the unchanging modifier added to attack rolls
- ExtraDamage is the weapon's critical extra dice: This can include bonus dice from the weapon's enchantment and/or bonus dice from the high crit property.
For a level 1 defender with longsword: To-hit is 4+3, damage 1d8+4: (1-(14+1-7-1)/20-.05)*(4.5+4)+(.05)*(8+4) = 5.70
(Defenders and other low-damage types fall within (8*1+24)/**8**=4
-(8*1+24)/**4**=8
4-8 damage.
For a level 1 barbarian with howling strike and a 1d12 executioner's axe: To-hit is 5+2, from stat+proficiency; a brutal 2 weapon drops the average by one, and adds 2; and rampage adds an extra basic attack on crit.
(1-(14+1-7-1)/20-.05)*( (5.5+2)+5+3.5 )+(.05)*(12+5+6+6.5+3.5)+(.05)*(1-(14+1-7-1)/20-.05)*( (5.5+2)+5)+(.05)*(12+5+6.5+3.5) = 12.97
on howling strike. So a level 1 barbarian is a "3 round striker" (HP estimate / DPR) which is quite accurate.
For assassins, they suffer from a number of problems: unspectacular dailies, a very swingy striker damage feature that doesn't scale with tier, and unimpressive at-wills, as per the guide. If you want a respectable damage assassin go with the Executioner assassin released in Dragon 394. However, individual builds may vary, and should be assessed using the above guidelines.
The enhancement bonuses would not stack (2 same typed bonuses). In fact the magical ammunition's enhancement bonus does indeed supersede the bonus from the weapon. The critical effect from the weapon will stack with the arrow's effect.
You can fire the magic ammo without "activating it" and use the weapon's enhancement bonuses but you cannot use the properties from the magic ammo.
The relevant section of the linked page answers the question fully and completely:
Ammunition applies an enhancement bonus to an attack roll and damage roll when used. If the projectile weapon is magical, use the ammunition's enhancement bonus in place of the weapon's enhancement bonus. The weapon's critical bonus and the properties from both the weapon and the ammunition still apply. Using magical ammunition doesn't prevent you from activating a magic weapon's powers.
Best Answer
Given the constraints of an interesting, high-damage, revenant at level 3. We first must discard the striker classes. While the idea of "striker" generally means high-damage, there are other ways to achieve high damage without it.
While it is always preferable to optimize a group over an individual, such that members can support each other, it sounds like your group has most of the "support" roles covered.
At level 3, most of the shennanigans possible with a revenant are quite limited. Getting access to half-elf's Dilettante is therefore contraindicated.
The most obvious "fun" build is one that maintains control of the battlefield while outside of their turn.
A revenant is +2 Con, +2 Dex/Cha. The "highest damage output" is easily a fire elementalist. At level 6, the top of the DPR king charts are dominated by thieves and rogues, especially ones that can trivially riposte.
That is, however, outside the scope of this effort due to the "interesting" restrictions.
In a trivial sense, we'll make you do damage by applying the charge-chassis. It's "boring" in a sense, but when combined with other features, it should make "who do I charge?" a meaningful choice to make every round.
At level 3, the charge chassis (in a non-thief) consists of: Melee basic attack, suprising charge +1[W] with CA (feat), Avalange hammer +1[W] on charge, bracers of mighty striking, +2 damage and the badge of the beserker.
While it would be a tempting trap to go dwarf as past-life race to pick up the ever cheesy dwarven weapon training, the fact that the revenant is not a strength-primary should be foremost in our minds.
Base class: knight. The knight (especially in low-mid heroic) is an exceptional defender as Sohum has shown in my weekly online game. We go revenant knight, past race tiefling. Tiefling is critical for us because the feat support is exceptional.
We must take a multiclass paladin feat and wrath of the crimson legion. This build would flow far more smoothly as a dwarf, but the revenant presents its own unique opportunities. The feats you will want in the future are: Weapon Proficiency(Mordenkrad), Two-handed weapon expertise, past-soul (tiefling) and Suprising charge.
For now, however, you have a knight that uses charisma as their primary stat, with dex as secondary (to qualify for surprising charge), wielding a maul. Every time she charges an enemy, you'll attack for 4d6+static modifiers + slow, have your knightly aura up to prevent movement (and your default MBA is a scary 2d6+static). This will make you the centre of attention, force you to pay attention every turn, as the aura violation is an opportunity attack, not interrupt, and will be a simple but tactically-enjoyable build.
Actual CBuilder paste coming later.