Haven't seen anyone else bring this up, so I figured I'd post some of the spoilers thus far that have caught my eye for Type 4.
Hypnotic Siren

Enchantment Creature- Siren
Bestow 5UU
Flying
You control enchanted creature.
Enchanted creature gets +1/+1 and has flying.
1/1
Another solid Control Magic effect and this one even leaves behind a chump blocker after the creature dies!
Polumorphus Rush

Instant
Strive — Polymorphous Rush costs

more to cast for each target beyond the first.
Choose a creature on the battlefield. Any number of target creatures you control each become a copy of that creature until end of turn.
I keep trying to get Mirrorweave to work in my stack but it's usually too situational. This one gives you more control over the effect, so it seems like it may work better.
Silence the Belivers

Instant
Strive — Silence the Believers costs 2B more to cast for each target beyond the first.
Exile any number of target creatures and all Auras attached to them.
An instant speed, exiling Plague Wind! I realize that this isn't
quite that, but it's close enough for me!
Worst Fears

Sorcery
You control target player during that player's next turn. Exile Worst Fears.
Haven't decided if this is going to replace Mindslaver (It's been a little too easy to recur sometimes) in my stack, or just be an extra effect, but I still want to try it.
Bearer of the Heavens

Creature--Giant
When Bearer of the Heavens dies, destroy all permanents at the beginning of the next end step.
10/10
On the fence about this guy, but he seems like he'd be a really good beatdown guy that makes your opponents hesitant about killing it. Then again, he might just have a huge target on his head from the guy who has little board presence.