magic guard doesnt remove positive effects, just removes (most) detrimental ones.How does Magic Guard interact with Poison Heal?
How does Magic Guard interact with Solar Power?
How do weather abilities interact with each other? Same for surge abilities.
magic guard will still let the user heal via leech seed/black sludge (as an example for PH).
solar power's effect should(grasping at "logic" straws for both, could be horridly wrong) be nullified, similarly to how life orb's/black sludge's negative recoil is stopped.
just to give better examples.