java.lang.NullPointerException: null
at java.util.Collections.addAll(Collections.java:5400) ~[?:1.8.0_51]
at lordmonoxide.gradient.items.Tool.getToolClasses(Tool.java:58) ~[Tool.class:?]
at vazkii.quark.tweaks.feature.DirtToPath.onRightClick(DirtToPath.java:40) ~[DirtToPath.class:?]
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_693_DirtToPath_onRightClick_RightClickBlock.invoke(.dynamic) ~[?:?]