New Dryad: 13 mana - Spawns a new Dryad from the waitlist. Cost increases with each purchase.
New Dryad Champion: 161 mana - Spawns a new Dryad from the waitlist. The summoned dryad will be one tier higher than usual. The +1 tier will be considered a "free upgrade" which does not influence the cost of future upgrades. This ability ignores waitlist priorities and picks a truly random player from the waitlist.
4 -> 13
Ummm, that is a +9... I am not getting any immediate vibes of where 9 could relate to 4. I think it will take more data to figure out the progression, which could always turn out to be G.M. fiat...
161 is quite a lot. There are acouple of bonuses though. we don't know how long it takes for tiers to cost more than 161, but from that point on champions will be better than mooks. Saving up for champs is a really really long-term investment though, at least at the current rate of progress.
It also bears noting that, unless I am missing something, S.N. only added this after summoning the player with a reserved spot, thus making it impossible for them to be a champion while pretending to be doing them a favour. Let us all marvel at this extremely subtle genius of malice.
The final bonus is that it is truly random, instead of being at the G.M.'s whim. I suspect that this alone is enough to make the seemingly high cost a bargain.
Finally, it does't say anything about cost increases. It may be that it is just omitted, and in fact it could be that the cost of summoning a champion increases if a non-champion is summoned! But by all appearances, it would seem that we can summon all our champons for 161 a pop while summoning flimsy baby dryads will get to that price quite swiftly with a couple more summons...