[Loriel]

The ability to turn invulnerable instantly at no cost is a major factor in the combat system.
Considering that bomies already possess a similar though not quite identical ability, it disadvantages them by reducing the usefulness of this ability. Other than that it might be argued that a battle where timing invulnerability is the deciding factor is a lot less fun than one that depends on traditional Graal combat prowess.

The simplest solution is to disable pausing completely. This would annoy people who legitimately use it to achieve a reasonable level of safety while shortly not paying attention to Graal, for whatever reason. However, this risk should be accepted by players, as a large part of Graal is about fighting and playerkilling and monsters. Migitating this risk, though, is possible by making use of the safe zones (noplayerkilling) spread through Graal.

Alternative options include limitting the usability of pausing, perhaps by introducing a "cooldown" that prevents pause from being used more than n times in a certain timespan, or a delay before pause, once activated, becomes effective. Coupled with weakening the player in these situations (taking double damage, being unable to move for five seconds afterwards, ...), this might make pausing unusable as a combat strategy.