minecraft 1.7.10
forge 10.13.4.1448
bloodmagic 1.3.3-17

After i tried to use sacrificial dagger at altar the game had crashed. I was able to return to my world but after swiching active item from dagger it crashed again, and countinue crashing every time i try to return to the world.
Link to logfile
Modpack is homemade.

Did you change Chisel versions recently?

No, it's rather old one (1.5.7). Latest chisel crashing game at start.

Are you using Chisel or Chisel 2. Cause if you're not using Chisel 2 I'd suggest upgrading.

Just chisel. Chisel 2 crashing the game at startup. Should i handle my chisel 2 issue then?

Yes, please. It seems the mod is sensing that Chisel is installed (it is) and then looks for a specific class that it is supposed to have. Since you have a much older version of chisel than the API that was used to build the mod, it tries to look for that class and cannot find it.

I will keep this issue open for a day until you get back to us! :D

The benifit of using Chisel 2 is that now (correct me if I've misinterperated this one, but I'm pretty sure this is what my experimants said) you can use any chiseled version of the structural blocks for the blood altar.

RED BEAM BEACONS FTW!

To clear up any confusion, you need to use the ChiselTeam fork of Chisel which can be found here. Not Cricket's fork.

I didn't realize I was using any non-Cricket fork API methods...

Problem with chisel 2 solved by updating forge. Looks like ChiselTeam chisel 2 works too or at least don't cause this crash. Now i know that i don't even prick myself, but put kinfe on the altar.