personally i wouldnt buy the freeze upgrade. the only usefully part of it is freezing air enemies because your soldiors find it hard to hit them. but it seems to make the gun overheat faster and make it slightly waeker
try this easy but wierd level
http://www.thegamehomepage.com/play/super-stacker-2/Wobble-weird/r0Y0Y004V7sr0Y0Y004V8lt0Y0Y005B6It0Y0Y1s4b6Kc0Y0Y004R6ir4m1s004R58r0Y1s006u3Fr0Y1s003b3Gt0J1H006C2At1H0J1s2W2wr1H0J1s5s3zr1H0J1s4c3zr1H0J2U4Q2qc1s1s004Q1ic0Y0Y00681Mc0Y0Y003y1Mc0u0u004Q4cc0u0u004Q3Ic0u0u004Q3ec0f0f005u68c0f0f004c68c0f0f004m5Yc0f0f005k5Yc0f0f005E5Yc0f0f00425Yc0u0u005Y2Ac0u0u003I2Ac0u0u005O18c0u0u003S18_t0J1H001r0J0J001r0J0J001r0J0J001r0J0J001/