When a monster is Successfully Summoned, the turn player is able to activate an Ignition Effect before the opponent can respond.
An Ignition effect is any effect that can only be activated in your Main Phase. For example, the first effect of “Lyla, Lightsworn Sorceress” is an Ignition Effect.
Example 1 - Basic Example
● If “Enishi, Shien's Counsellor” is Summoned, its effect can be activated,
before the opponent can activate “Bottomless Trap Hole”.
● Then, Bottomless can be activated as CL2.