This game features eight playable characters, with four starting preset teams of two and unlockable individual character modes. When playing with the character pairs, one character fires when unfocused, while the other switches in and fires when focused, with a reduction in movement speed. The two shot types can be drastically different. The individual characters, with the exception of Remilia and Youmu, do not change shot types while focusing/unfocusing.
Imperishable Night features Last Spells. For the enemy, a Last Spell is a bonus Spell Card which the player can challenge without the option to use bombs and without the risk of losing lives. On the player side, Last Spells are secondary "bomb" Spell Cards, which last longer and do much more damage than normal bombs at the expense of two bomb stocks. Player Last Spells can only be used immediately after being hit, with a grace period of less than 1 second.
Additionally, there is a "Time Orb" system which affects the story/score, as well as a gauge which tracks how human/youkai (normal/focused) you are and determines how you can collect more time orbs.