Charnel Troll - very weak Mystic for GRN

Hey guys,

So I had the "good fortune" of pulling Charnal Troll twice yesterday (first using mana jewels and then from a pack).  

I understand that perhaps you wanted to balance the fact that MTG PQ troll only needs to exile one creature from the graveyard (as opposed to multiple trolls needing more feeding in paper mtg) but you've changed a Rare 3 drop with good stats (and a strong balance factor) into a mythic 14 mana 5/5 with a downside.

There are tons of Green and Black creatures at the same or lesser cost that have equal or better stats or little to no drawback-- and with removal being so easy, the fact that it can grow each turn, provided you've seeded your graveyard, isn't much help:

It seems like this should be a 9 cost 4/4 (to generally match the paper magic) at the very least, though again that's fairly pathetic.  I suppose it just seems like it should be a low-cost beater with a big penalty (i.e. the exile) or it's entirely useless.

As examples of better Green & Black creatures (in Standard) with equal or cheaper cost (and many as equally text-heavy):

Mythic:

Isareth the Awakener (12 cost 5/5)
Sanctum Seeker (13 cost 5/5)
Tendershoot Dryad (14 cost 5/5, big benefit)
Izoni Thousand-Eye (14 cost 4/5 with strong benefit)
Doom Whisperer (14 cost 6/6)
Circu (14 cost 5/6 with benefit)

Rare:

Territorial Allosaurus (11 cost 5/6)
Vine Mare (12 cost 6/4 with benefit)
Dread Shade (12 cost 5/5 with benefit)
Swarm Guildmage (13 cost 5/5 with benefit)
House Guildmage (13 cost 5/5 with benefit)
Conclave Guildmage (13 cost 5/5 with benefit)
Champion of Dusk (13 cost 5/5 with benefit)
Aryel, Knight of Windgrace (13 cost 5/5 with benefit)
Ripjaw Raptor (14 cost 5/6 with benefit)
Kothophed (14 cost 6/6 with benefit)
Grunn the Lonely King (14 cost 5/5 with benefit)
Graveblade Maurauder (14 cost 4/7 with strong benefit)
Goreclaw, Terror of Qal Sisma (14 cost 5/4 with strong benefit)
Emperor's Vanguard (14 cost 6/5 with strong benefit)
Dwynen, Gilt-Leaf Daen (14 cost 5/6 with benefit)

Uncommon:

Conclave Cavalier (14 cost 5/5 with benefit)