Trying My Free Ticket in Tournament in Soulkeep

I want to try tournament for first time and I have rented 3 cards to be able to deal with this tournament which seems to be easy but needs to be inderstood first, I have started it with only 3 towers as It seems to be played with only towers with levels as My common towers have level 0.

At all I have take a general impression about what tournament going like to be, It has only one way and no strange fiends they are like common battles that I have played but there are some rules as you can see below.

BATTLE RULES

SPEEDSTER: Extra speed for fiends, more with each new wave
10% PER WAVE

MAGIC DISPELLER: Magical resistance for fiends goes up each new wave
8% PER WAVE

I started the tournament with only 115 mana and this was a new surprise to me as I can not use Amped which has 160 mana so I have used Quakemaker but with fast mana it can do nothing as it have fire interval with 4 seconds and this is too long.

So what I have learned is to rent cards with high levels to be able to put them in the range and also I have to rent some spells with level 3 or above and I intend first to look for Gloom owl with higher level to be able to deal with fast fiends and also charnel pit and may be I find stew of doom or cheapo this would be great as I could use Amped with its 160 mana with less than that and be able to defend against the first wave.

It is so motivating to play and to be in the list below and earn some tokens and What I really playing for is for fun until I become more experienced with all of rules and all of fiends.