Talk:Fusion Reports/@comment-5297252-20121117065931/@comment-5051663-20121117220801

For fusion success vs. fusion failure (ignoring wanted dino), the probability of success is (110% - #crystals_to_guarantee_fusion) in percent. That puts a lvl 4 + lvl 4 fusion at 33%, and lvl 10 + lvl 10 at 75%. This comes from the game files, although I really should look at these again to make sure they haven't changed. My actual experience, almost all at lvl 4 + lvl 4, is 75 successes out of 226 fusions attempted, which is darn close to 33%. The average number of tries to a success would be 100%/%_chance_of_success, which for lvl 4 + lvl 4 would be 3.03 tries. This doesn't mean that you won't get stuck with a running streak of 11 failures.

As far as biome goes, it seems from the reported tables that the game chooses a random biome from those 2 or 3 eligible, then independently choses dino from within that biome. From this, you can calculate the chance of getting a wanted dino from each biome: #_wanted_dinos / total_#_dinos * 100%. Now average those numbers for the eligible biomes of the fusions you are going to do. I am less sure that the dinos chosen from within the biome have equal probability. For lack of specifics, I'm assuming that all dinos within a tier/biome combination have equal probability.

The basic lessons from this are: (1) want more than one dino at a time, preferably in different biomes of the same tier. (2) try to choose your fusion so that no matter which eligible biome comes up, you have a chance to get something you want, and (3) you're stuck with what you've got to fuse, so either choose the best fusion or wait until you have more choices.

Example: you want 1 of 7 tier 1 forest dinos (14%) and 1 of 2 tier 1 desert dinos (50%). The obvious choice here is forest + desert, which gives you 32% of getting something you want. Your next best choices are desert + air or desert + tundra, which give you 25% of getting the desert dino you wanted. Fusions like tundra + tundra or air+air give you 21% chance of getting something you want.

I wonder about the random number generator also. I had 27 random hatches at the start of the game with no Mammoths, rather annoying when the game challenges you to hatch a *mammoth* in a timed challenge.