Arcane Spike is the fourth upgrade of Path 1 for the Wizard Monkey in BTD6. It allows the Wizard's magic bolts to deal extra damage to M.O.A.B. Class Bloons, dealing 16 damage per shot to M.O.A.B. Class Bloons. It also pops 5 layers of damage to normal bloons as well, allows the tower to pop Lead Bloons, and attack twice as fast as Arcane Mastery. It costs $8,500 on Easy, $10,000 on Medium, $10,800 on Hard, and $12,000 on Impoppable.
A 4-0-2 Arcane Spike is more effective than the 4-2-0 Arcane Spike because the Arcane Spike upgrade itself has a low pierce, making Intense Magic significantly increase the pierce and is better than adding new weapons that don't buff the original energy bolt.