Originally Posted by jars
and? kassadin isn't an AD champion
His W gives him pretty reasonable damage. 90 + .15 AP on max rank. Of course, before you get around maxing it, it really won't do much (though early game, of course, his physical damage with just base values is still significant as his base damage is actually pretty **** high at 56-123), but even the 30 points from the first rank (that I admittedly get a bit late; it might be prudent to get it before maxing out E or Q but I really like to maximize his kiting damage and creep clearance first) can be a rather big deal.
I'm usually not terribly afraid of wading into melee against anything but melee glass cannons with him (against those it's obviously most efficient to just kite and burst since they can't do **** and it's only one-two comboes for the kill) and lategame you are talking about, if not carry-level, at least Tanky DPS level melee damage that gets pretty massive if you do take magic hits.
We're talking ~140 bonus damage at RoA+Deathcap (-15 per level of W you're missing) with ~100-120 base and and 150 damage with the magic part having significant penetration if we build Voidstaff, slightly more (~155) and procs for ~420 bonus every 2 secs if we build Lichbane instead. Given tanky DPSs often end the game with ~250-300 AD and about ~30% crit chance (Trinity + Atma's), Kassadin does a decent approximation especially with Lichbane.