I have tried the game. I claimed the Rookie Chest.

I have won three 0.10 Tavern Coins. I played "Goblin Prince" once, which I lost, but I also played "The Blind Rune" twice, and I won both times. 0.104 Steem twice, so 0.208 Steem. And if I count the 0.001 Steem after I lost my first "Goblin Prince" game, then I won 0.209 Steem with this game without investment.

But investing into this kind of game would be gambling, and I am no longer gamble (Magic Dice and Epic Dice were enough), so I will not invest any Steem into the "Tavern Games", nor any other gambling game.