Infernotail

Infernotails do 9 damage to the zombie they hit and 3 splash damage to nearby zombies. A direct hit to a vehicle or robot will melt it instantly, killing it. Splash cannot melt vehicles or robots, but will just do 3 damage. It can't melt bosses, even if they are robotic. Infernotails can be used to kill Plasamwing, Bombers and other ultra-annoying zombies.

Strategy
Infernotails are at least 9 times more powerful than ordinary Cattails, as the spikes have splash damage in a 3x3 area. If a Plasmawing shows up, this may be your only hope of killing it. Use this to kill any annoying zombies, such as Bungees, Gigas, Bombers, Zombonis and others. 2-4 should help you survive for a long number of flags in Survival: Endless.