Atarlost |
Closest you can get is Acid Arrow at 2d4/3 levels. You aren't going to kill anyone quickly with it though. On the bright side you don't have to wait for spell blending.
All the other no SR stuff I can find is save/half stuff like pellet blast, which isn't going to work with spellstrike even with the close range arcana.
Cult of Vorg |
Words of power acid has a 2nd level up to 5d4 with half again next round, but close arcana needed just like acid arrow.
The 0th level acid is a no SR 1d3 just like acid splash, but can be melee so no close range needed, useful if the GM house rules against arcane mark.
Web Bolt from the ARG isn't damage and also needs the close arcana, but it's a 1st level no SR single target web.