If you already have Frog, Doge and Snek go for rune. But if you don't have all three of them, might want to consider get them via summon shop. These 3 can be fit in most team at current meta.
Even if you already have that summon there are still chances you gonna get a dupe so it's 1/11 chance to get it from pull while collecting it.
You can lower the risk by only start to buy summon frag after you pull a gold from summon treasure to reset the counter.

Power until your all lvl 7+ runes
You will eventually get all the summons off free draws.
18k pts (or 1 gold summon) is 6 lvl 5 runes, or 3 lvl 6 runes, which is quite a boost in power This post was last edited by ber***@hotmail.com at 2017-1-13 13:25

Your statement is misleading, as the power gain will be off "upgrade rune" as opposed to "new rune"
6 lv 5 rune gives three times as much stat as upgrading 6 lv 5s into lv 6s, and that's what people will actually get. It's still a nice amount since it affect all your chars, effectively an extra awakening or so on your entire team, but it's not as drastic as you make it sound.

The OP can test this themselves, simply by removing an equal number of runes and seeing how much power is loss. The result of power gain will be similar assuming the OP is still sitting on level 4-5 runes.

In the end, runes are similar to magas, the stopping point before the power:cost ratio diminishes is at least level 6 to 7, i'd say 7 because of how accessible summons points are.

For most players, obtaining a new summon is of course the funnest way to go abouts spending these pts, but speaking from the standpoint as a top player in my server, if you're in on this game in the long run, get those summon runes first. I'm already on my 6th gold summon off free draws and summon seals obtained from events. You will eventually pull duplicates should you chose to buy a gold summon from the summon shop, and the net difference is 14 000 pts lost as a duplicate gold summon only nets you 4 000 pts, and i'm 6 for 7 in terms of non-duplicate gold summon pulls.

Btw can I ask you this? Do you sell low level rune for point and buy lv 5 of different kind of rune? Or you don't sell any rune at all?

Post intercepted.
If runes are the way to go, should I aim for the level 5 runes or level 3?
Kinda curious on what's best power to summon points ratio.

The level 5 one

Thanks for all the suggestions everyone, appreciate this.

A small correction: Buying a new summon with point costs 16x1800 = 28800 points, while pulling a duplicate of the gold summon gives 4000 points, so thats about 25k points lost.

I'm more inclined towards power as well. So far, have 5 gold summons - Gamaken, Serpent, Dog of hell, Eight span bird and Fukurokomaru.

Over the span of 5 months of playing, have ac*ulated like 40k points now. Guess I'll go for the runes then.

Only reason I'm hesitating now, is because there is a 4th summon tab now. Giving runes to this new slot will obviously be better, but we don't know when it will be available.

As i'm all level 6 runes, and my nin/atk ones are level 7, I do sometimes sell off some extra runes to get back 80% of the point value. As for level 3 vs level 5, they're the same. You do not get a higher discount purchasing a level 5. 4 level 3 runes cost you 3000 which can be merged into a level 5.

The gold summons i've gotten from free draws and summon seals off events are:
Monkey King x2, Flood Dragon, Eight Span Bird, Gamaken, Lightning Tiger, Dog of Hell
& Kirin (which I bought)

To this day I am glad I made the decision back then to go for runes rather than more gold summons.

Yes my bad on the math, and yes that's quite a large correction.

28800 points is 9.6 lvl 5 runes which translates to a nice power boost

Always Go For Runes ! :D