crafting question

if i want get Enemies you Kill have a #% chance to Explode, which is crusader influence. do i first need to get a crusader influence base item? basically how do i craft it.

You can either get a crusader base and use normal crafting methods to spam rolls until you hit the mod, or you can get a Crusader's Exalted Orb, and use it to slam a single random crusader mod onto a non-influenced base.

Using the influence slam can be powerful, since you can first craft the item to your other requirements and control where the slam hits by filling the prefixes or suffixes to prevent it from going to the wrong one. Depending on the mod, you can also look at multi-modding to bench craft a blocking affix for deterministic outcomes.

You can practice on the emulator at: https://www.craftofexile.com/