Give Abyssal Scepter an indicator like Frozen Heart.

Currently, when you buy a frozen heart and an enemy is within range to have their attack speed reduced by the aura it looks like this

Unlike that helpful little snowflake, the aura for abyssal scepter that decreases Magic Resist looks like this

Yep, nothing there.

Even the little blue magic resist shield with a red X through it would be great.