Level up your tailed Beast(Summon)
What is my tailed Beast and why is it important?
Your tailed beast adds stats (Force, Chakra, Speed, Power) to your whole team when you are doing pvp events or arena.
Someone has a Matatabi and I only have Shukaku!
You too can get Matatabi, all you need to do is level Shukaku up to 10 and press the transform button.
How do I show my tailed beast in town and in fights?
In the summon window there is a 'display' button, this will make your beast appear.
How much silver, channel scrolls, gold should I invest in tailed beasts?
You should never use gold on a tailed beast if you can help it. Channeled scrolls can be used in place of gold and have a chance to trigger the L Crit which will give your beast the rest of the XP needed to reach its next level. Channeled scrolls can also trigger S Crits for 10x XP. Spend leftover silver here when you are able. Try to use channeled scrolls when your beast is just beginning a new level since L Crits take you to the next level at 0 XP, after using a bunch you should level the rest of the way with silver since silver can trigger S Crits. Also try and save your channeled scrolls for Matatabi since the cost per level goes up considerably whereas Shukaku is pretty cheap to level.
Disclaimer: this guide is opinion based with some facts pulled from the game itself, if you disagree with a view posted here you're quite welcome to disregard this guide.