Bug Boost spell: Prolonged effect / expires one round after intended expiry

[Steve]

The Boost effect of the Power Ring sometimes is still active even though there was already the message that everything returned to normal.
I recognized it during my solos, when my characters still did a good damage although they shouldn't,and afterwards also in normal playthroughs but only on a emulator so I don't know if this is a rom glitch or also on a Genesis.
Another thing I realised is that you can only recognize this glitch if you look at the damage a character does because if you look at the stats of the character the effect vanish immediatly (tested it), otherwise it can stay up to 5 turn after the message (that was what I got with abusing save states)
And the last thing is that I only know it works with the Power Ring boost but I don't know if this effect can also happen when using the Attack spell.

Note: I cannot find the exact post, but I do recall RubixCuber explaining that such an issue may be too time consuming to fix as it is not an issue with the editor, but with the core game.

(source)