-CER
All verbs ending in -cer conjugate like nacer, shown below, except the regular verbs coercer, ejercer, (con)vencer and mercer, for which see the note #1 below and the radical-changing verbs escocer, (re)torcer, for which see note #2 below. In all other verbs ending in -cer c>zc before a or o.  All forms are as for a regular -er verb except for the following (bracketed forms are regular):

Imperative:

 (usted) nazca, (usteded) nazcan

Present indicative:

 nazco, (naces, nace, nacemos, nacéis, nacen)

Present subjunctive:

 nazca, nazcas, nazca, nazcamos, nazcáis, nazcan

Note #1

 Infinitives ending in -zar, -cer and -cir.
z is spelt c before i or e.
c is spelt z before a or o (although in the majority of verbs ending in -cer, c becomes zc before a or o).

Note #2

 Cocer (to boil), torcer (to twist), destorcer (to untwist) and retorcer (to wring) , conjugate exactly like mover (to move) except for the predictable spelling change c>z before a, o (bracketed forms are regular).

Imperative:

 (tu) cuece, (usted) cueza, (usteded) cuecen

Present indicative:

 cuezo, cueces, (cocemos) (cocéis), cuecen

Present subjunctive:

 cueza, cuezas, cueza, (cozamos), (cozáis), cuezan