325 gems for 35 cells
100% chance at 50 cells of 1 of 5 monsters for $12.
Nemesis chests are $7 for a 50% chance at 1 of 3 monsters.
$30 (800 gems) for a random diamond relic (mostly bad)
I don't know what the odds are to get what you want, but i know they aren't good.
I admit to being suckered a few times by these offers (Nemesis chests) but these prices and odds have really been an incentive NOT to spend money
Not to mention these monsters do not have a long shelf life. Gorg has been out 2-3 weeks now and Hookai the maze monster counters all of Gorg's moves while dealing a load of damage himself, IMO he's better than Gorg, definitely more versitile.