[Pyro]

In its current state, fortunite is similar to guarding. You use the last momentum at the end of your turn to activate it.
However, that is where the similarities end.

60% DR combined with an inability to be affected by status effects, be guard broken, or hit by evasion ignoring attacks means that for the price of an emerald, you have five turns of 60% additional DR with five item belt slots. This is applicable to both evade users and tanks, and in fact, is even more effective when used by the latter due to their weaknesses (over time damage, primarily) being nullified for an entire turn, alongside the damage resistance.

I believe that raising the cost to 3 momentum and/or giving it a cooldown similar to explosion are decent approaches to rectifying the issue, as scarcity has and never will be worth considering.