Originally Posted by Motas
Heimer's only support move is the turrets, and that takes time to truly be effective.
Morgana only has the black shield to support.
One support ability does not a support hero make...
That's like playing Warwick support because he has a global AS buff
Epic Warwick Support Strategy
I think I can help riot out by pointing out why they deem them support over Mage per-say. First of all, almost all the champions can be played a variety of ways, so its hard to really pick just one aspect of them that they want to label them as, but they tend to label things based on what they consider is the champion's most outstanding role.
Why is Heimer a Support?
-His passive increases the health regeneration of nearby units, and thus provides additional duration of champions in lanes and fights
-His grenade not only blinds, but also stuns the center target if hit by it, in turn you are disabling the enemy team to give your team a better chance at fighting with them
-His turrets are not necessarily a defensive measure, but they are sure as hell a good boost to your lane tower defenses, thus providing a safe place for your team to fight and providing a defensive 'line'
-His ultimate makes him a little more of a support, not saying its purely for support, but by upgrading to armor reducing turrets, your making your opponents weaker for your teammates to take out
His rockets are his only outstanding (as in the ability that stands out, not the best) dps ability
Why is Morgana a Support?
-Her skill shot disable disables an opponent to make it easier for your team to take them out, it doesn't do as much damage directly as it does in just making it impossible for the target champion to not move as your allies beat down on him
-Her Spell shield (no need to describe it)
-Her Ultimate, why does a significant amount of damage, is much more usefully seen as a aoe stun, which when your stunning your enemies, your making it easier for your allies to hurt them
Her aoe decay ability is her only really outstanding damage ability, but it is also in theory a support ability, since it weakens all the opponents for your allies